roll out vs flatten

roll out is a noun but flatten is not a noun.

Word	Noun	Adjective	Verb	Adverb
roll out	Yes	No	Yes	No
flatten	No	No	Yes	No

As verbs, flatten is a hypernym of roll out; that is, flatten is a word with a broader meaning than roll out:

roll out (noun)	flatten (noun)
the act of officially distributing a new product or service to the public

roll out (verb)	flatten (verb)
flatten or spread with a roller	become flat or flatter
straighten by unrolling	make flat or flatter
to distribute systematically or strategically	lower the pitch of (musical notes)
officially distribute a new product or service to the public