extrusion vs caput

extrusion and caput both are nouns.

Word	Noun	Adjective	Verb	Adverb
extrusion	Yes	No	No	No
caput	Yes	No	No	No

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

extrusion: something that bulges out or is protuberant or projects from its surroundings
caput: a headlike protuberance on an organ or structure

Other hyponyms of extrusion include frontal eminence, occipital protuberance, belly, mogul, nub, nubble, snag, wart.

extrusion (noun)	caput (noun)
squeezing out by applying pressure	the upper part of the human body or the front part of the body in animals; contains the face and brains
something that bulges out or is protuberant or projects from its surroundings	a headlike protuberance on an organ or structure