Attacker builds sea lairs (8)

I believe the answer is:

assailer

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'attacker' is the definition.
Both the answer and definition are singular nouns.
Maybe there's a link between them I don't understand?

'builds sea lairs' is the wordplay.
'builds' indicates an anagram (I've seen 'build' mean this).
'sea'+'lairs'='sealairs'
'sealairs' anagrammed gives 'ASSAILER'.

Can you help me to learn more?

(Other definitions for assailer that I've seen before include "Aggressive sort" , "One attacking" .)

I've seen this clue in The Hindu.

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