As Leolaia has mentioned above, the Watchtower "translators" of the NW"T" [which is another way of saying Freddy Franz] can stoop to blurring the distinction between "etymology" and "application" or "meaning" when it suits their purpose. The way words are used by the speakers of a language determines the meaning of words. In this regard most speakers then, as now, would be unaware of the etymology of the words they used but whose meaning would be accepatble with common practice.
A good example of this blurring comes with the word "Apo-luthrosis" which had a simple meaning in NT times, which even Franz acknowledged. The etymology of the word is "apo" - "away from" - and "luthrosis" - "ransom" which I suppose can literally be rendered as " a getting away [from someone] on the payment of a ransom". Because "ransom" is one of the Watchtower's favourite buzz words, they render this word as "release by ransom" six times, with "release by the ransom [paid]" once, [at Ro 3:24].
However, by NT times, the idea of an actual payment seems to have completely disappeared and the meaning simply came to be "deliverance" [as Franz acknowledged at Luke 21:28]
We see the same tactic here with "nouthesia". The etymology derives from "nous" mind, and "thesia" which Vine suggests could mean "put into". But that is not the way the word was used by the speakers who applied the word in the first century. The emphasis was not on the mind of the person so much, as the action that created an atmosphere of training. As Phizzy mentioned above, the word simply meant to "admonish" or "to train by word" which is contrasted with "training by act". "Training by word" could take the form of an "instruction" or in the face of danger, "a warning".
The word occurs three times in the NT, and Freddy used three separate "translations" to convey the meaning of this word:
1Cor 10:11 - "Warning"
Eph 6:4 - "mental regulating"
Titus 3:10 - "admonition"
Which gives him no excuse. He was aware that the word really meant "admonition".