Limpet and rocks firmly fixed (9)

I believe the answer is:

implanted

'firmly fixed' is the definition.
(to implant is to fix in place)

'limpet and rocks' is the wordplay.
'rocks' indicates an anagram.
'limpet'+'and'='limpetand'
'limpetand' anagrammed gives 'IMPLANTED'.

(Another definition for implanted that I've seen is " Embedded".)

I've seen this clue in The Guardian.

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