sketch vs description

sketch and description both are nouns.

Word	Noun	Adjective	Verb	Adverb
sketch	Yes	No	Yes	No
description	Yes	No	No	No

As nouns, description is a hypernym of sketch; that is, description is a word with a broader meaning than sketch:

sketch (noun)	description (noun)
preliminary drawing for later elaboration	sort or variety
short descriptive summary (of events)	the act of describing something
a humorous or satirical drawing published in a newspaper or magazine	a statement that represents something in words
a brief literary description

sketch (verb)	description (verb)
describe roughly or briefly or give the main points or summary of
make a sketch of