Minor carpeting upset university teacher (4)
I believe the answer is:
guru
'teacher' is the definition.
(I know that Guru is a type of teacher)
'minor carpeting upset university' is the wordplay.
'minor carpeting' becomes 'rug' (rug can mean a small carpet).
'upset' shows that the letters should be reversed in order.
'university' becomes 'u' (abbreviation for university).
'rug' in reverse letter order is 'gur'.
'gur'+'u'='GURU'
(Other definitions for guru that I've seen before include "Master, mentor" , "Hindu or Buddhist spiritual teacher" , "Hindu or Sikh religious teacher or leader" , "Influential expert" , "Wise leader" .)