sit down vs hunker

sit down and hunker both are verbs.

Word	Noun	Adjective	Verb	Adverb
sit down	No	No	Yes	No
hunker	No	No	Yes	No

As verbs, hunker is a hyponym of sit down; that is, hunker is a word with a more specific, narrower meaning than sit down:

sit down: be in a position in which one's upper body is largely upright and supported by one's backside
hunker: sit on one's heels

Other hyponyms of sit down include lounge, sprawl, perch, rest, roost, crouch, hunker down, scrunch, scrunch up, squat.

sit down (verb)	hunker (verb)
show to a seat; assign a seat for	sit on one's heels
be in a position in which one's upper body is largely upright and supported by one's backside
take a seat