Like 007 said proskyneo can carry the meaning of showing obedience and lowering oneself, ex.2 Samuel 14:4 and 1 Samuel 25:23,24 respectively. Still it is used in the sense that denotes true and full religious worship, which is a proskyneo that is unique and acceptable only to God.
There are times when God's representatives rejected proskyneo.
- Acts 10:24,25 "When Peter entered, Cornelius met him, and fell at his feet and worshiped him. But Peter raised him up, saying, "Stand up; I too am just a man."
- Revelation19:9,10 "Then he said to me, "Write, 'Blessed are those who are invited to the marriage supper of the Lamb '" And he said to me, "These are true words of God." Then I fell at his feet[the angel that was delivering the message to John] to worship him But he said to me, "Do not do that; I am a fellow servant of yours and your brethren who hold the testimony of Jesus; worship God. For the testimony of Jesus is the spirit of prophecy." "
- Revelation 22:8,9 same as above
If it is ok to accept proskyneo as long as you are a representative of God, why would they reject proskyneo. It only stands to reason that there is a way that proskyneo can be given, even if directed to one of God's representatives, that is not acceptable. This is to say that proskyneo can and does carry a meaning of full and true worship that only God can receive.
An example of proskyneo that could only be acceptable if directed to God, which is clearly different than proskyneo in the Samuel accounts, is found in Revelation 4:9-11. It says, "And when the living creatures give glory and honor and thanks to Him who sits on the throne, to Him who lives forever and ever, the twenty-four elders will fall down before Him who sits on the throne, and will worship Him who lives forever and ever, and will cast their crowns before the throne, saying, "Worthy are You, our Lord and our God, to receive glory and honor and power; for You created all things, and because of Your will they existed, and were created." The main difference is that they gave God glory, honor, power, and praise for His creation; these things in proskyneo are unique to God.
I doubt that anyone would not agree that to proskyneo anything other than God in the manner found in Rev. 4:9-11 would be idolatrous.
If they do not agree and we can proskyneo something other than God in the manner of Rev. chapter 4, how can we tell what is unique about proskyneo directed to God. If we could proskyneo something other than God in the manner of Rev. chapter 4, there would be nothing in proskyneo that could not be given to representatives of God. If this were true no representative would have grounds for rejecting any type of proskyneo. However there was rejection of proskyneo by God's representatives in Acts and Revelation, as cited earlier.
This same unique manner proskyneo found in Rev. 4:9-11 is found in the next chapter of revelation verses 6-14; though this time Jesus as the Lamb is the object of this proskyneo . It says, "And I saw between the throne (with the four living creatures) and the elders a Lamb standing, as if slain, having seven horns and seven eyes, which are the seven Spirits of God, sent out into all the earth. And He came and took the book out of the right hand of Him who sat on the throne. When He had taken the book, the four living creatures and the twenty-four elders fell down before the Lamb, each one holding a harp and golden bowls full of incense, which are the prayers of the saints. And they sang a new song, saying, "Worthy are You to take the book and to break its seals; for You were slain, and purchased for God with Your blood men from every tribe and tongue and people and nation. "You have made them to be a kingdom and priests to our God; and they will reign upon the earth." Then I looked, and I heard the voice of many angels around the throne and the living creatures and the elders; and the number of them was myriads of myriads, and thousands of thousands, saying with a loud voice, "Worthy is the Lamb that was slain to receive power and riches and wisdom and might and honor and glory and blessing." And every created thing which is in heaven and on the earth and under the earth and on the sea, and all things in them, I heard saying, "To Him who sits on the throne, and to the Lamb, be blessing and honor and glory and dominion forever and ever." And the four living creatures kept saying, "Amen " And the elders fell down and worshiped."
Notice what the proskyneo toward God involves in chapter 5, "Worthy are You, our Lord and our God, to receive glory and honor and power; for You created all things, and because of Your will they existed, and were created." Then to the Lamb in chapter 4, "Worthy is the Lamb that was slain to receive power and riches and wisdom and might and honor and glory and blessing." And every created thing which is in heaven and on the earth and under the earth and on the sea, and all things in them, I heard saying, "To Him who sits on the throne, and to the Lamb, be blessing and honor and glory and dominion forever and ever." "
The same things that are unique proskyneo to God are attributed to Jesus, namely glory, honor, and power. Also, these things are not attributed thought the Lamb to God, rather they are attributed directly to both the Lamb and God.