Daughter, female relative to cow (5)
I believe the answer is:
daunt
'to cow' is the definition.
(I've seen this in another clue)
'daughter female relative' is the wordplay.
'daughter' becomes 'd' (genealogical abbreviation).
'female relative' becomes 'aunt' (I've seen this in another clue).
'd'+'aunt'='DAUNT'
(Other definitions for daunt that I've seen before include "Scare off - dismay" , "Cause to feel intimidated" , "Cow" , "Dishearten" , "Make (someone) apprehensive" .)