Limitless treats consumed by thin relative (5-4)

I believe the answer is:

great-aunt

'relative' is the definition.
(great-aunt is a kind of relative)

'limitless treats consumed by thin' is the subsidiary indication.
'limitless' says to take the centre.
'consumed by' indicates putting letters inside.
'thin' becomes 'gaunt' ('gaunt' can be similar in meaning to 'thin'**).
The centre of 'treats' is 'reat'.
'reat' put into 'gaunt' is 'greataunt'.

(Another definition for great-aunt that I've seen is " Tag nature (anag) - relative".)

I've seen this clue in The Independent.

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