The Fennas word for sea is moir. Moir is a last name. In Manx (a recently extinct but now revived Celtic language) moir means mother, queen.
How did I come up with this word? The Welsh word for sea is môr, the Irish words for sea are farraige and muir, and the Breton word for sea is mor. In addition, the Cornish word for sea is mor, and the Scottish Gaelic words for sea are muir, fairge and cuan.