u-drive vs letting

u-drive and letting both are nouns.

Word	Noun	Adjective	Verb	Adverb
u-drive	Yes	No	No	No
letting	Yes	No	No	No

As nouns, letting is a hypernym of u-drive; that is, letting is a word with a broader meaning than u-drive:

Other hypernyms of u-drive include lease, rental.

u-drive (noun)	letting (noun)
a rented car	property that is leased or rented out or let