Pressure to remove last horse from moorland (4)
I believe the answer is:
heat
'pressure' is the definition.
(I've seen this in another clue)
'remove last horse from moorland' is the wordplay.
'remove last' means to remove the last letter (I've seen 'removing last' mean this).
'horse' becomes 'h' (synonyms).
'from' becomes 'ex' ('from' in Latin).
'moorland' becomes 'at' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'h'+'ex'='hex'
'hex' with its final letter taken off is 'he'.
'he'+'at'='HEAT'
'to' is the link.
Can you help me to learn more?
(Other definitions for heat that I've seen before include "Preliminary race to qualify finalists" , "Energy that caues a rise in temperature" , "High temperature" , "Warm up" , "Preliminary round in a contest" .)