whitewash vs hush up

whitewash is a noun but hush up is not a noun.

Word	Noun	Adjective	Verb	Adverb
whitewash	Yes	No	Yes	No
hush up	No	No	Yes	No

As verbs, whitewash and hush up are synonyms defined as:

Other synonyms of whitewash include gloss over, sleek over.

whitewash (noun)	hush up (noun)
a specious or deceptive clearing that attempts to gloss over failings and defects
wash consisting of lime and size in water; used for whitening walls and other surfaces
a defeat in which the losing person or team fails to score

whitewash (verb)	hush up (verb)
exonerate by means of a perfunctory investigation or through biased presentation of data	cause to be quiet or not talk
cover with whitewash	cover up a misdemeanor, fault, or error
cover up a misdemeanor, fault, or error