soliloquize vs speak

soliloquize and speak both are verbs.

Word	Noun	Adjective	Verb	Adverb
soliloquize	No	No	Yes	No
speak	No	No	Yes	No

As verbs, speak is a hypernym of soliloquize; that is, speak is a word with a broader meaning than soliloquize:

Other hypernyms of soliloquize include talk.

soliloquize (verb)	speak (verb)
talk to oneself	express in speech
	exchange thoughts; talk with
	use language
	give a speech to
	make a characteristic or natural sound