loosen vs stiffen

loosen and stiffen both are verbs.

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

loosen (verb)	stiffen (verb)
become loose or looser or less tight	become stiff or stiffer
make loose or looser	make stiff or stiffer
make less dense	severely restrict in scope or extent
disentangle and raise the fibers of
cause to become loose
become less severe or strict
make less severe or strict