"The Lorax" author (5)
I believe the answer is:
seuss
'the lorax author' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for seuss that I've seen before include "Dr. --, US children's author" , "Dr -, children's author (The Cat in the Hat)" , "8 [DOCTOR]" .)