chess move vs castling

chess move and castling both are nouns.

Word	Noun	Adjective	Verb	Adverb
chess move	Yes	No	No	No
castling	Yes	No	No	No

As nouns, castling is a hyponym of chess move; that is, castling is a word with a more specific, narrower meaning than chess move:

Other hyponyms of chess move include castle, capture, check, checkmate, mate, gambit.

chess move (noun)	castling (noun)
the act of moving a chess piece	interchanging the positions of the king and a rook