string up vs gibbet

string up is not a noun while gibbet is a noun.

Word	Noun	Adjective	Verb	Adverb
string up	No	No	Yes	No
gibbet	Yes	No	Yes	No

As verbs, gibbet is a hyponym of string up; that is, gibbet is a word with a more specific, narrower meaning than string up:

Other hyponyms of string up include halter.

string up (noun)	gibbet (noun)
	alternative terms for gallows

string up (verb)	gibbet (verb)
add as if on a string	hang on an execution instrument
kill by hanging	expose to ridicule or public scorn