Obstinate or stupid (7)
I believe the answer is:
asinine
I believe this is a double definition.
'obstinate' is the first definition.
(I've seen this in another clue)
'stupid' is the second definition.
(I've seen this before)
(Other definitions for asinine that I've seen before include "Jenny's often like this" , "In the nature of supposedly stupid animal" , "Absurd" , "Silly like a donkey" , "'Mindless, vacuous (7)'" .)