talk down vs speak

talk down and speak both are verbs.

Word	Noun	Adjective	Verb	Adverb
talk down	No	No	Yes	No
speak	No	No	Yes	No

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

Other hypernyms of talk down include talk.

talk down (verb)	speak (verb)
belittle through talk	express in speech
speak in a condescending manner, as if to a child	exchange thoughts; talk with
direct and control (the flight of an airplane during landing) via radio	use language
	give a speech to
	make a characteristic or natural sound