In plain terms, lay to rest (5)

I believe the answer is:

inter

'lay to rest' is the definition.
(synonyms)

'in plain terms' is the wordplay.
'in' indicates a hidden word.
'INTER' is hidden in the letters of 'plain terms'.

(Other definitions for inter that I've seen before include "Plant" , "Place into grave, tomb" , "Bury (or, perhaps, Milan)" , "Entomb" , "Prefix meaning in the middle" .)

I've seen this clue in the Sydney Morning Herald.

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