Equal beat at climbing tor (10)
I believe the answer is:
tantamount
'equal' is the definition.
(similar in meaning)
'beat at climbing tor' is the wordplay.
I cannot really understand how this works, but
'beat' could be 'tan' (I've seen this before) and 'tan' is located in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for tantamount that I've seen before include "Equal in value" , "Equivalent in value (to)" , "Virtually equivalent (to)" , "Equivalent in seriousness (to)" .)