unbend vs loosen

unbend and loosen both are verbs.

Word	Noun	Adjective	Verb	Adverb
unbend	No	No	Yes	No
loosen	No	No	Yes	No

As verbs, loosen is a hypernym of unbend; that is, loosen is a word with a broader meaning than unbend:

Other hypernyms of unbend include loose.

unbend (verb)	loosen (verb)
release from mental strain, tension, or formality	become loose or looser or less tight
become less tense, rest, or take one's ease	make loose or looser
make less taut	make less dense
free from flexure	disentangle and raise the fibers of
unfasten, as a sail, from a spar or a stay	cause to become loose
straighten up or out; make straight	become less severe or strict
	make less severe or strict