There's something in climbing; it sort of grows on one (4)
I believe the answer is:
limb
'there's something in climbing it sort' is the definition.
I can't tell whether this definition defines the answer.
'grows on one' is the wordplay.
'grows' becomes 'mb' (I can't justify this - if you can you should give a lot more credence to this answer).
'on' is a charade indicator (letters next to each other).
'one' becomes 'li' (I've seen this in other clues).
'mb' after 'li' is 'LIMB'.
'of' is the link.
Can you help me to learn more?
(Other definitions for limb that I've seen before include "Branch of a tree (risky to go out on)" , "Jointed appendage" , "Large tree branch" , "Branch - arm - leg" , "Tentacle" .)