Long summer aid to get high (6)

I believe the answer is:

ladder

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

'aid to get high' is the definition.
I can't judge whether this defines the answer.

'long summer' is the wordplay.
'long' becomes 'l'.
'summer' becomes 'adder' (someone who adds or does sums).
'l'+'adder'='LADDER'

Can you help me to learn more?

(Other definitions for ladder that I've seen before include "ranking table" , "sometimes with companion" , "Household climbing device or tear in stocking" , "Unravel (as stocking)" , "1 [UNLUCKY FOR SOME]" .)

I've seen this clue in The Hindu.

Want a hint initially instead of a full solution? Install my app