As a noun, "linn" means pool or pond in Irish. "Dia linn" is one thing you can say after someone sneezes, equivalent to "bless you" (though Linn doesn't mean pool in that context!). It is also one quarter of the expression "Beidh ár lá linn" or "We shall have our day".
― Anonymous User 3/11/2009
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Lin/n could also be a short form of names like Ingelin, Irmelin and Iselin.