A horny male caught in rain, perhaps Romeo (8)
I believe the answer is:
paramour
'romeo' is the definition.
(thesaurus)
'a horny male caught in rain' is the wordplay.
'horny male' becomes 'ram' (male sheep. I am not sure about the 'horny' bit.).
'caught in' means one lot of letters goes inside another.
'rain' becomes 'pour' (pouring is a kind of raining).
'a'+'ram'='aram'
'aram' put inside 'pour' is 'PARAMOUR'.
'perhaps' acts as a link.
Can you help me to learn more?
(Other definitions for paramour that I've seen before include "Lover, usually illicit" , "Kept woman" , "fancy woman" , "A married person's secret lover" , "Lover, especially of a married person" .)