Affected by nausea (7)
I believe the answer is:
bilious
'affected by nausea' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for bilious that I've seen before include "Affected by illness, yellowgreen?" , "Caused by excessive secretion from the liver" , "Nauseated; irritable" , "Bad-tempered or maybe just sick" , "Liverish - irritable" .)