Christmas stocking vs stocking

Christmas stocking and stocking both are nouns.

Word	Noun	Adjective	Verb	Adverb
Christmas stocking	Yes	No	No	No
stocking	Yes	No	No	No

As nouns, stocking is a hypernym of Christmas stocking; that is, stocking is a word with a broader meaning than Christmas stocking:

Christmas stocking: a stocking that is filled with small Christmas presents
stocking: close-fitting hosiery to cover the foot and leg; come in matched pairs (usually used in the plural)

Christmas stocking (noun)	stocking (noun)
a stocking that is filled with small Christmas presents	the activity of supplying a stock of something
	close-fitting hosiery to cover the foot and leg; come in matched pairs (usually used in the plural)