To a Pole, it's a high speed (3)
I believe the answer is:
ton
'a high speed' is the definition.
'ton' can be an answer for 'speed' (I've seen this before). I'm not certain of the 'a high' bit.
'to a pole' is the wordplay.
'a pole' becomes 'n' (abbreviation for North, as in North Pole).
'to'+'n'='TON'
'it's' acts as a link.
Can you help me to learn more?
(Other definitions for ton that I've seen before include "20cwt" , "Two thousand, two hundred and forty lbs avoirdupois" , "Unit of weight equivalent to 2240 pounds" , "1000 kilos" , "A slang 100 mph" .)