hook vs cup hook

hook and cup hook both are nouns.

Word	Noun	Adjective	Verb	Adverb
hook	Yes	No	Yes	No
cup hook	Yes	No	No	No

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

Other hyponyms of hook include boat hook, buttonhook, crotchet, fishhook, gaff, gig, meat hook, skyhook, bolus hook.

hook (noun)	cup hook (noun)
a short swinging punch delivered from the side with the elbow bent	hook (usually on the underside of a shelf) for hanging cups
a golf shot that curves to the left for a right-handed golfer
a basketball shot made over the head with the hand that is farther from the basket
a curved or bent implement for suspending or pulling something
a mechanical device that is curved or bent to suspend or hold or pull something
a catch for locking a door
anything that serves as an enticement
a sharp curve or crook; a shape resembling a hook

hook (verb)	cup hook (verb)
approach with an offer of sexual favors
entice and trap
secure with the foot
to cause (someone or oneself) to become dependent (on something, especially a narcotic drug)
fasten with a hook
catch with a hook
hit with a hook
hit a ball and put a spin on it so that it travels to the left
make a piece of needlework by interlocking and looping thread with a hooked needle
make off with belongings of others
take by theft
rip off; ask an unreasonable price