libretto vs script

libretto and script both are nouns.

Word	Noun	Adjective	Verb	Adverb
libretto	Yes	No	No	No
script	Yes	No	Yes	No

As nouns, script is a hypernym of libretto; that is, script is a word with a broader meaning than libretto:

libretto: the words of an opera or musical play
script: a written version of a play or other dramatic composition; used in preparing for a performance

Other hypernyms of libretto include book, playscript.

libretto (noun)	script (noun)
the words of an opera or musical play	a written version of a play or other dramatic composition; used in preparing for a performance
	a particular orthography or writing system
	something written by hand

libretto (verb)	script (verb)
	write a script for