Grass around middle of Everest is support for climbers (7)
I believe the answer is:
trellis
'support for climbers' is the definition.
(I've seen this before)
'grass around middle of everest' is the wordplay.
'grass' becomes 'betray' (I've seen this before).
'around' says to take the centre.
'middle of everest' becomes 'ellis' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
The central letters of 'betray' are 'tr'.
'tr'+'ellis'='TRELLIS'
'is' is the link.
Can you help me to learn more?
(Other definitions for trellis that I've seen before include "Structure supporting climbing plants" , "Frame for creepers" , "Framework - stiller (anag)" , "Light framework for climbing plants" , "trainer" .)