get the picture vs understand

get the picture and understand both are verbs.

Word	Noun	Adjective	Verb	Adverb
get the picture	No	No	Yes	No
understand	No	No	Yes	No

As verbs, understand is a hypernym of get the picture; that is, understand is a word with a broader meaning than get the picture:

get the picture (verb)	understand (verb)
get the meaning of something	know and comprehend the nature or meaning of
	perceive (an idea or situation) mentally
	believe to be the case
	make sense of a language
	be understanding of