Murmur and ridicule such a hill (7)

I believe the answer is:

hummock

'such a hill' is the definition.
(hummock is a kind of hill)

'murmur and ridicule' is the wordplay.
'murmur' becomes 'hum' (I've seen this before).
'and' means one lot of letters go next to another.
'ridicule' becomes 'mock' (I've seen this before).
'hum'+'mock'='HUMMOCK'

(Another definition for hummock that I've seen is " small rise".)

I've seen this clue in The Telegraph.

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