A male expert including one, cold but friendly (8)
I believe the answer is:
amicable
'friendly' is the definition.
(associated in meaning)
'a male expert including one cold' is the wordplay.
'male' becomes 'm' (common abbreviation).
'expert' becomes 'able' (able can mean expert or talented).
'including' indicates putting letters inside.
'one' becomes 'i' (Roman numeral).
'cold' becomes 'C' (eg on taps).
'm'+'able'='mable'
'i'+'c'='ic'
'mable' enclosing 'ic' is 'micable'.
'a'+'micable'='AMICABLE'
'but' acts as a link.
(Other definitions for amicable that I've seen before include "not hostile" , "Friendly, nonthreatening" , "Friendly and good-tempered" , "In friendly spirit" , "Friendly, good-humoured" .)