short castling vs castle

short castling and castle both are nouns.

Word	Noun	Adjective	Verb	Adverb
short castling	Yes	No	No	No
castle	Yes	No	Yes	No

As nouns, castle is a hypernym of short castling; that is, castle is a word with a broader meaning than short castling:

Other hypernyms of short castling include castling.

short castling (noun)	castle (noun)
Castling on the kingside.	interchanging the positions of the king and a rook
	a large building formerly occupied by a ruler and fortified against attack
	(chess) the piece that can move any number of unoccupied squares in a direction parallel to the sides of the chessboard
	a large and stately mansion

short castling (verb)	castle (verb)
	move the king two squares toward a rook and in the same move the rook to the square next past the king