Crossword Genius

The setter's two older relatives climbing mountain (5,4)

Ross

I believe the answer is:

nanda devi

I'm a little stuck... Click here to teach me more about this clue!

'mountain' is the definition.
(I've seen this before)

I cannot understand how the remainder of the clue works.

Can you help me to learn more?

(Another definition for nanda devi that I've seen is " mountain".)

I've seen this clue in The Telegraph.
Want a hint initially instead of a full solution? Install my app