sock vs sweat sock

sock and sweat sock both are nouns.

Word	Noun	Adjective	Verb	Adverb
sock	Yes	No	Yes	No
sweat sock	Yes	No	No	No

As nouns, sweat sock is a hyponym of sock; that is, sweat sock is a word with a more specific, narrower meaning than sock:

sock: hosiery consisting of a cloth covering for the foot; worn inside the shoe; reaches to between the ankle and the knee
sweat sock: a sock worn for athletic events

sock (noun)	sweat sock (noun)
hosiery consisting of a cloth covering for the foot; worn inside the shoe; reaches to between the ankle and the knee	a sock worn for athletic events
a truncated cloth cone mounted on a mast; used (e.g., at airports) to show the direction of the wind

sock (verb)	sweat sock (verb)
hit hard