Spare tyre limp -- grease added for repair (6-3,6)

I believe the answer is:

middle-age spread

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'spare tyre' is the definition.
I don't know anything about this answer so I cannot judge whether it can be defined by this definition.

'limp grease added for repair' is the wordplay.
'for repair' indicates an anagram (the letters must be fixed).
'limp'+'grease'+'added'='limpgreaseadded'
'limpgreaseadded' with letters rearranged gives 'MIDDLE-AGE SPREAD'.

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(Other definitions for middle-age spread that I've seen before include "Pot" , "Weight problem for those growing older" , "Weight gain in later life" .)

I've seen this clue in The Guardian.

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