Husband gets university fellows in a bad mood (4)
I believe the answer is:
huff
'bad mood' is the definition.
(someone 'in a huff' is in a bad mood)
'husband gets university fellows' is the wordplay.
'husband' becomes 'h' (abbreviation).
'gets' means one lot of letters go next to another.
'university' becomes 'U' (abbreviation for university).
'fellows' becomes 'ff' (an abbreviation for fellow written twice).
'h'+'u'+'ff'='HUFF'
'in a' acts as a link.
(Other definitions for huff that I've seen before include "State of having taken offence" , "Pique - remove from board" , "Fit of petty annoyance" , "Fit of petulance - encountered playing draughts?" , "Fit of annoyance or ineffectual bluster" .)