I have gone to a lot of trouble to clear this up once and for all. I have looked up the Greek word genea: "generation" of Matt. 24:34, as well as the related Hebrew word dour: "generation" in the best and most up-to-date dictionaries and lexicons. If there is an overlap, these distinguished gentlemen would certainly have mentioned it, I'm sure. So here goes. Be warned, it is a long and tedious post. Interestingly, the related Hebrew word describes a closed circle, which would not allow for an overlap. If an overlap was meant, the author would have used the plural phrase "these generations (geneoun)". As you will see, that is not the case. Also most of the time, the NT writers refer to the wicked generation of Jews of his day which will be adversely judged. Thirty seven years later they were destroyed by the Roman armies.
Bauer, Danker (BDAG)
2 . genea: sum total of those born at the same time, expanded to include all those living at a given time and freq. defined in terms of specific characteristics, generation, contemporaries (Hom. et al.; BGU 1211, 12 [II BC]); Jesus looks upon the whole contemp. generation of Israel as a uniform mass confronting him (cp. Gen 7:1; Ps 11:8) Mt 11:16;12:41f;23:36;24:34 ;Mk 13:30;Lk 7:31;11:29-32,50f;17:25;21:32 (EGraesser, ZNW Beih. 22, 2 ’60). S. also 1 above. This generation is characterized Mt 17:17; Mk 9:19 D; Lk 9:41;Mk 9:19;Mt 12:45;16:4 D; Lk 11:29;Mt 12:39;16:4; Mk 8:38 (JGuillet, RSR 35, ’48, 275-81). Their contemporaries appeared to Christians (the latter term as Mt 17:17;Mk 9:19 v.l.; Lk 9:41, the former Ac 2:40; cp. Ps 77:8) Phil 2:15 (Dt 32:5).—Cp. Wsd 3:19. A more favorable kind is mentioned in Ps 23:6; 111:2; 1QS 3:14.—The desert generation Hb 3:10 (Ps 94:10). after he had served his own generation Ac 13:36; 1 Cl 5:1; 19:1; the first generation (of Christians) Hs 9, 15, 4 (Paus. 7, 4, 9 in the fourth generation).
3 . genea the time of a generation, age (as a rule of thumb, the time between birth of parents and the birth of their children; since Hdt. 2, 142, 2; Dionys. Hal. 3, 15; Gen 50:23 ; Ex 13:18; 20:5; EpJer 2; Philo, Mos. 1, 7; Jos., Ant. 5, 336; SibOr 3, 108). Here the original sense gradually disappears, and the mng. ‘a period of time’ remains.
Friberg Lexicon
291 genea strictly birth, the circumstances relating to one's origin; (1) literally, those descended from a common ancestor race, clan, descendants (perhaps AC 8.33); as an ethnic group kind (LU 16.8); (2) generally, all those living at the same time generation, contemporaries (MT 12.41); (3) the time span of one generation age, generation, period (MT 1.17); (4) specifically in AC 8.33's quotation from Isaiah 53.8 Septuagint, possibly origin; more probably posterity, descendants
Barcley-Newman
1267 genea f generation, contemporaries; period, age (of time) ; family, posterity (posterity or perhaps origin Ac 8.33)
1.4 people living at the same time and belonging to the same reproductive age-class - 'those of the same time, those of the same generation.' 'the people of this generation will be punished' Lk 11.51.
The expression 'the people of this generation' may also be expressed as 'the people living now' or 'the people of this time.' Successive generations may be spoken of as 'groups of people who live one after the other' or 'successions of parents and children.'
Liddell & Scott (abridged)
8862genea
I. of the persons in a family ,
1. race, stock, family, Hom., etc.; Il. according to his family, Ib.; by birth-right, Od.; by descent, Il.:-of horses, a breed, Ib.:-generally, in kind, Hdt.:-also a tribe, nation, Aesch.
2. a race, generation, Il.
3. offspring, Orac. ap. Hdt.; and of a single person, Soph.
II. of time or place in reference to birth:
1. a birth-place, Il.; of an eagle's eyrie, Od.
2. age, time of life, esp. in phrases youngest, eldest, in age, or by birth, Hom.
3. time of birth, Hdt.; Xen.
Thayer Lexicon
1124 genea
(crf. Curtius, p. 610); the Septuagint often for dour; in Greek writings from Homer down;
1. a begetting, birth, nativity : Herodotus 3, 33; Xenophon, Cyril 1, 2, 8, etc.; (others make the collective sense the primary significance, see Curtius as above).
2. passively, that which has been begotten, men of the same stock, a family; a. properly, as early as Homer; equivalent to Gen. 31:3, etc. Josephus, Antiquities 5, 1, 5. the several ranks in a natural descent, the successive members of a genealogy: Matt. 1:17, Philo, vit. Moys. i. sec. 2). b. metaphorically, a race of men very like each other in endowments, pursuits, character; and especially in a bad sense a perverse race: Matt. 17:17; Mark 9:19; Luke 9:41; 16:8; (Acts 2:40).
3. the whole multitude of men living at the same time : Matt. 24:34 ; Mark 13:30; Luke 1:48; 21:32; Phil. 2:15; used especially of the Jewish race living at one and the same period: Matt. 11:16; 12:39,41f,45; 16:4; 23:36; Mark 8:12,38; Luke 11:29f,32,50f; 17:25; Acts 13:36; Heb. 3:10; Luke 7:31; Luke 11:31; who can describe the wickedness of the present generation, Acts 8:33 (from Isa. 53:8 the Septuagint) (but cf. Meyer, at the passage).
4. an age (i. e. the time ordinarily occupied by each successive generation), the space of from 30 to 33 years (Herodotus 2, 142, et al.; Heraclitus in Plutarch, def. orac. c. 11), (Plutarch, the passage cited); in the N. T. common in plural: Eph. 3:5 (Winer's Grammar, sec. 31, 9 a.; Buttmann, 186 (161)); in ages gone by, Acts 14:16; for ages, since the generations began, Col. 1:26; from the generations of old, from ancient times down, Acts 15:21; unto generations of generations, through all ages, forever (a phrase which assumes that the longer ages are made up of shorter): Luke 1:50 R L, Isa. 51:8; ibid. T Tr WH equivalent to Ps. 89:2f; Isa. 34:17; very often in the Septuagint; (add, Eph. 3:21, cf. Ellicott at the passage) (is used of a century in Gen. 15:16, cf. Knobel at the passage, and on the senses of the word see the full remarks of Keim, iii. 206 (v. 245 English translation)).*
LEH Lexicon
823 genea
Gn 6,9; 7,1; 9,12; 15,16; 17,7
generation Gn 6,9; family Gn 31,3; offspring Ex 12,14; age 1 Mc 2,61
*Zph 3,9 for her generation?
NIDNTT; TWNT
Balz-Schneider Lexicon (EDNT)
1. Of the 43 references to genea in the NT, 33 are in the Synoptics, where the word refers in 25 of its occurrences to the Jewish people in the time of Jesus, 17 times in the expression "this generation." In the redactional comment on the genealogy of Jesus in Matt 1:17 and in the Magnificat in Luke 1:48, 50, genea means the generations to follow; in Luke 16:8, it refers to membership in a particular class.
2. The Synoptic form "this generation" comes from the later Hellenistic Q stratum, which directs its polemic toward Israel as the last generation before the end and proclaims to it the approaching judgment. Jewish apocalyptic literature employs corresponding motifs and forms of speech. Thus 1 Enoch 93:9 refers to a rebellious generation, 1QHab 2:6f. to a last generation, and Jub. 23:16ff. to an evil generation. Matt 11:16 par. Luke 7:31 begins the Q simile of the children's game, the meaning of which — that the divine wisdom has no longer given authority to Israel, but rather to John and Jesus — adopts and stresses a Deuteronomic (Deut 32:5) and Wisdom (Pss 77:8; 94:10 LXX) motif. Matt 23:36 par. Luke 11:50f. appears in a Wisdom saying that takes up a complaint against wisdom that has been despised (Prov 1:24-33; Bar 3:12f.; 11QPs. a 18:8, 15; 1 Enoch 93:8; 94:5; 4 Ezra 5:9f.); as an early Christian prophetic saying, it accuses the last generation of Israel of filling the multitude of the sins of the fathers through the murder of the prophets, including the murder of Zechariah the son of Berechiah (Josephus B.J. iv.335).
This same condemnation increases in the complex of sayings about the sign of Jonah: Matt 12:39 par. Luke 11:29 calls this generation evil; Matthew adds, as also in Matt 16:4, that it is a totally adulterous generation. The Q form is repeated in Matt 12:42 par. Luke 11:31 and Matt 12:41 par. Luke 11:32 in the twofold threat referring to the Queen of the South and the Ninevites. In addition, Matthew intensifies the statement by connecting it with the warning against relapse and calls Israel an evil generation. Luke 11:30 adds to the statement with the reference to the Son of Man who comes in judgment.
Mark transforms the demand for a sign in Q into the refusal of a sign from heaven. For Mark 8:12 only the final judgment awaits the condemned Israel of the time of Jesus . Thus in 8:38 he calls it an adulterous and sinful generation. Consequently in an apocalyptic threatening word 13:30 affirms, along with Matt 24:34 and Luke 21:32, that this generation must experience the horrors of the end time . Luke 17:25 connects this with the fixed plan of God promised in Scripture. Mark 9:19 has Jesus sigh in exasperation over this evil (even perverse, according to Matt 17:17 and Luke 9:41) generation.
Moulton-Milligan
genea
The collective sense of this word—involved in its historic relation to genos—is normal throughout, and survives in MGr “race, lineage.” Thus it denotes a family, without individual reference: P Oxy I. 104 11 (a will—A.D. 96) “his issue” (should he himself predecease)—similarly PSI III. 240 6 (ii/A.D.) … in a will—ib. IV. 713 16 (A.D. 97) “their joint issue,” P Hal I. 1 217 (iii/B.C.) “no one may swear by any other oath [than Zeus, Hera and Poseidon], nor offer it, nor may he bring forward his family,” i.e. to swear by them: see note, p. 121. Syll 856 16, 18 (ii/B.C.) of a manumitted slave, Cagnat IV. 915 C 4 (i/A.D.) The abstract sense appears in P Tebt II. 312 6 (A.D. 123–4) “exempted priest of the [.]4th generation.”
Gingrich
1327 genea
clan, race, kind Lk 16:8. Generation, contemporariesMt 12:41f; 17:17; Mk 9:19; 13:30; Lk 21:32; Hb 3:10. Age, period of time Mt 1:17; Lk 1:48, 50; Col 1:26. Perh. family or origin Ac 8:33. [pg 38]
Liddell & Scott (unabridged)
µ genea , Ion. Ep. dat. Il.14.112:
I. of the persons in a family,
1. race, family, Il.20.306, cf. Od.1.222, 16.117; Il.15.141; 20.203, cf. 214; higher by birth or blood, 11.786 (but younger in Archil.ap.Sch.ad l.); of this race and blood, Il.6.211; 10.68; by birthright, Od.1.387; by descent, Il.23.471; 21.187; descent from, ib.157; Hdt.2.134; of horses, breed, stock, Il.5.265,268: pl., families, Plu.Tim.34; to have issue, GDI1798 (Delph.), ib.1152 (Elis): hence, tribe, nation, A.Pers.912 (lyr.), Eleg.2:— rare in Prose, X.Cyr.1.1.6; SIG 306.8 (Tegea, iv B.C.)
2. race, generation, Il.6.146; I.250, etc., cf. Hdt.2.142, Th.1.14, Heraclit.ap.Plu.2.415e (but, Id.ap.Lyd.Mens.3.14); SIG1015.6 (Halic.); age, the historical, opp. to the mythical, age, Hdt.3.122; D.H.3.15.
3. offspring, ll.21.191, Orac.ap.Hdt.6.86, S.Aj.189 (lyr.); of a single person, (i.e. Pelias) Pi.P.4.136, cf. I.8(7).71.
4. metaph., class, kind, Pl.Phlb.66b; Plot.5.1.7.
II. of Time or Place,
1. birthplace, Il.20.390, cf. Od.1.407; of an eagle's eyrie, 15.175.
2. age, time of life, Il.14.112; 6.24,9.161, Od.19.184.
3. after Hom., time of birth, Hdt.3.33,4.23; X.Cyr.1.2.8. [pg 342]
In Septuagint often for Hebrew dour
BDBLex
2082 dour [2083] (Hebrew) (page 189) (Strong 1755)
† I. n.m.: Dt 32:5 period, generation, dwelling (cf. sub vb. supr.; also NH, Aram. (incl. B Aram.) dor , age, generation; Ar. dawrun gyrus, orbis, periodus; Sab. one time, once each, once in a year 1. period, age, generation, mostly poet.: a. of duration in the past, former age(s) Is 51:9; Dt 32:7; b. usually of duration to come, future ages; c. apparently including both past and future; 2. of men living at a particular time (period, age), generation, as transitory Ec 1:4: specific. a. in the present, and (or) the past Gn 7:1 (J) Ex 1:6 (P) Nu 32:13 (JE) Dt 1:35, 2:14, Ju 2:10, 2:10, Is 53:8 (cf. Che crit. n.) Je 2:31; also Psalm 95:10, Jb 8:8, Is 41:4. b. Ju 3:2 (present & future); cf. pl. Gn 6:9 (i.e. his own gen. and those immediately contiguous, before and after). c. esp. of a future generation Gn 15:16 (JE), with numeral, cf. Dt 23:3, 23:4, 23:9; also Dt 29:21, Psalm 48:14, 71:18, 78:4, 78:6, 102:19, 109:13, Jo 1:3 cf. Psalm 22:31, 22:32 (Che crit. n.); of a succession of generations Psalm 145:4; Est 9:28; usually pl. Gn 9:12 (P); with num. Psalm 105:8 = 1 Ch 16:15; Dt 7:9; v. further, of posterity, Jb 42:16; usually pl. c. sf. Gn 17:7, 17:9, 17:12, Ex 12:14, 12:17, 12:42, 16:32, 16:33, 27:21, 29:42, 30:8, 30:10, 30:21, 30:31, 31:13, 31:16, 40:15, Lv 3:17, 6:11, 7:36, 10:9 (all P); 17:7, 21:17, 22:3, 23:14, 23:21, 23:31, 23:41, 23:43, 24:3, 25:30, (all H); Nu 9:10, 10:8, 15:14, 15:15, 15:21, 15:23, 15:38, 18:23, 35:29, Jos 22:27, 22:28 (all P). 3. generation characterized by quality or condition, class of men: crooked generation Dt 32:5 (song) cf. v:20, Psalm 78:8, 78:8, Je 7:29; of diff. classes of wicked, Pr 30:11, 30:12, 30:13, 30:14 cf. Psalm 12:8; of the righteous, as a class Psalm 14:5, 24:6, 73:15 112:2; so also i.e. the dead Psalm 49:20 (so most; yet v. infr. sub 4). 4. dwelling-place, habitation Is 38:12 cf. vb., so Saad Ki Ges De Che RVm (Ew life); so also Psalm 49:20 De Witt, cf. Che:OP 479.
HALOT
028 dour
II dour also dor, (160 x): I (:: Albright BASOR 163:50f: Arb. dahr a long time); MHb.; Ug. dr (|| phär, mphärt ) collection (Pope 48, 60; Neuberg JNES 9:215ff; UTGl. 697; Aistleitner 786 generation); Ph.: family DISO 60; Arm. generation ï BArm., Sam. BenH. 2:445, Mnd. (MdD 100b); Arb. daur period, OSArb. occasion; Eth. daÒr and doÒr (loan < Heb. ?, Leslau 16); Akk. daÒru eternity from daruÒ to last, continue, (Ug. duÒru, daÒru, dariÒtu PRU 3:218), daÒru generation WSem. lw. AHw. 164b: Is 51 8 Ps 72 5 102 25 †, Ex 40 15 , 4Q as in Sir 44 1 (Textus 2:99):
—1. sing. cycle, lifetime, descent, generation, (all the people who have grown up in the period from the birth of a man until the birth of his first son ; Noth Überl. St. 21; a period with particular events and people, Ped. Isr. 1-2:490): Gn 7 1 15 16 , as long as a thousand generations Dt 7 9 , 29 21 , Jb 8 8 ; with Dt 32 5 , with Ps 14 5 ; with 49 20 , with 73 15 , with Jr 7 29 etc.; Ex 3 15 and Dt 32 7 (29 x; Ug. drdr, ana duÒrim, ana daÒri duÒri and simil., for ever, (PRU 3:218) Akk. duÒr daÒri , simil. in Mnd.) and Ps 145 4 generation after generation, Ps 102 25 , cj. Ps 71 18 ; group Ps 24 6 ; Is 53 8 ? fate (Arb. daÒÀirat ), alt. his contemporaries, cj.
—2. pl. generations (in Greek originally counted as forty years, from the time of Herodotus as thirty-three and a third years , Meyer Gesch. 3/2:207): Jb 42 16 , Ju 3 2 , future generations descended from us Jos 22 27f ; generations in times past Is 51 9 ; according to his (their, your) generations = generation after generation descended from him (them, you) Lv 25 30 Gn 17 7 . 12 ; among his contemporaries Gn 6 9 , Sir 44 1 (alt.: in his turn);
—Ju 3 2 dl. (dittogr., Seeligmann VT 11:214 2 ); Jr 2 21 ?, prp. Sept., Latina; Is 41 4 r ( ï v. 22 ).
Is 51 8 Ps 72 5 102 5 †, sf.— 1. sg. circuit, lifetime, generation (from a man’s birth to the birth of his first son; the totality of (adult) contemporaries; a time with its noteworthy events & people): haddôr hazzeh Gn 7 1 ; l®°elef dôr to the 1000th gener. Dt 7 9 ; dôr dôr Ex 3 15 , dôr w¹dôr Dt 32 7 , & dôr l®dôr Ps 145 4 gener. to gener.; — 2. pl. generations: dœrôtênû °aµrênû the generations coming after us Jos 22 27 ; b®dœrœt¹yw among his contemporaries Gn 6 7 . (pg 69)
Harris (TWOT)
(418a) dûrcircle, ball.
(418b) dour , dor generation.