Remaining seaport bombed (2,5)

I believe the answer is:

to spare

'remaining' is the definition.
(thesaurus)

'seaport bombed' is the wordplay.
'bombed' indicates anagramming the letters.
'seaport' with letters rearranged gives 'TO SPARE'.

(Another definition for to spare that I've seen is " Left over".)

I've seen this clue in The Times.

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