plunge vs set out

plunge is a noun but set out is not a noun.

Word	Noun	Adjective	Verb	Adverb
plunge	Yes	No	Yes	No
set out	No	No	Yes	No

As verbs, set out is a hypernym of plunge; that is, set out is a word with a broader meaning than plunge:

Other hypernyms of plunge include begin, commence, get, get down, set about, start, start out.

plunge (noun)	set out (noun)
a brief swim in water
a steep and rapid fall

plunge (verb)	set out (verb)
begin with vigor	take the first step or steps in carrying out an action
devote (oneself) fully to	lay out orderly or logically in a line or as if in a line
cause to be immersed	depart for someplace
immerse briefly into a liquid so as to wet, coat, or saturate
thrust or throw into
fall abruptly
drop steeply
dash violently or with great speed or impetuosity