Ill-tempered taxi driver having to cross river (6)
I believe the answer is:
crabby
'ill-tempered' is the definition.
(synonyms)
'taxi driver having to cross river' is the wordplay.
'taxi driver' becomes 'cabby' (I've seen this before).
'having to cross' indicates putting letters inside.
'river' becomes 'r' (abbreviation for river).
'cabby' placed around 'r' is 'CRABBY'.
(Other definitions for crabby that I've seen before include "Peevish" , "Ill-tempered" , "Bad-tempered, irritable" , "Lrritable, bad-tempered" , "Ill-natured" .)