groom vs smarten up

groom is a noun but smarten up is not a noun.

Word	Noun	Adjective	Verb	Adverb
groom	Yes	No	Yes	No
smarten up	No	No	Yes	No

As verbs, smarten up is a hyponym of groom; that is, smarten up is a word with a more specific, narrower meaning than groom:

groom (noun)	smarten up (noun)
a man who has recently been married
someone employed in a stable to take care of the horses
a man participant in his own marriage ceremony

groom (verb)	smarten up (verb)
care for one's external appearance	dress and groom with particular care, as for a special occasion
give a neat appearance to	make neat, smart, or trim
educate for a future role or function