thicken vs modify

thicken and modify both are verbs.

Word	Noun	Adjective	Verb	Adverb
thicken	No	No	Yes	No
modify	No	No	Yes	No

As verbs, modify is a hypernym of thicken; that is, modify is a word with a broader meaning than thicken:

Other hypernyms of thicken include alter, change.

thicken (verb)	modify (verb)
become thick or thicker	make less severe or harsh or extreme
make thick or thicker	add a modifier to a constituent
make viscous or dense	cause to change; make different; cause a transformation