quetch vs crab

quetch is not a noun while crab is a noun.

Word	Noun	Adjective	Verb	Adverb
quetch	No	No	Yes	No
crab	Yes	No	Yes	No

As verbs, crab is a hyponym of quetch; that is, crab is a word with a more specific, narrower meaning than quetch:

quetch (noun)	crab (noun)
	a stroke of the oar that either misses the water or digs too deeply
	decapod having eyes on short stalks and a broad flattened carapace with a small abdomen folded under the thorax and pincers
	a louse that infests the pubic region of the human body
	the edible flesh of any of various crabs
	a quarrelsome grouch

quetch (verb)	crab (verb)
express complaints, discontent, displeasure, or unhappiness	complain
	fish for crab
	scurry sideways like a crab
	direct (an aircraft) into a crosswind