Poles always seem unimpressed! (5)
I believe the answer is:
sneer
'seem unimpressed' is the definition.
I can't tell whether this defines the answer.
'poles always' is the wordplay.
'poles' becomes 'SN' (North and South poles).
'always' becomes 'eer' (poetic way of saying ever).
'sn'+'eer'='SNEER'
Can you help me to learn more?
(Other definitions for sneer that I've seen before include "Speak scornfully" , "Contemptuous gesture" , "Taunt" , "Curl one's lip" , "A scornful expression or remark" .)