What is the difference “in the nude” vs “nude”? [closed]

The two sentences have the same meaning, but the grammar is different.

I caught them watching TV in the nude.

The adjective "nude" is here a fused determiner head in the preposition phrase "in the nude" -- an idiom meaning "naked". Indirectly then, "nude" is a kind of predicative adjunct (or complement) with “them” as predicand.

I caught them watching TV nude.

Again, "nude" is an adjective, though here more clearly functioning as a predicative adjunct with the object "them" as predicand.

It would be more correct to refer to the persons in the incident as 'naked', actually. 'Nude' refers to an unembarrassing situation, not one which is inappropriate.

https://www.quora.com/What-is-the-difference-between-naked-and-nude-if-any

'Nude' refers to the human form, as such. 'Naked' draws attention to the fact that it is unclothed, and - generally speaking - it would be expected to be clothed.

'Naked' derives from the Old English meaning 'bare, empty, not fully clothed'.

http://www.etymonline.com/index.php?term=naked

'Nude' is the late Middle English from the Latin nudus, meaning 'plain or explicit'. [Quoted from my Oxford Dictionary of English]