Any of several marine mammals of the order Sirenia, including the manatee and dugong.

A marine mammal of any of several genera in the family Otariidae (the eared seals). / (heraldry) A monster consisting of the upper part of a lion combined with the tail of a fish.

Any of many polyps, of the order Actiniaria, which occurs in marine and estuarine habitats, and which captures its food using tentacles

An echinoderm of the class Holothuroidea, with an elongated body and leathery skin.

(rare) Alternative form of sealion (“engage in disingenuous debate”)

Any of many marine echinoderms, of the class Echinoidea, commonly found in shallow water, having a complex chewing structure named Aristotle's lantern.

(geography) An inland sea bound by Southeastern Europe in the west, Eastern Europe in the north and northeast, and Turkey in the south.

The body of water between Japan and the Asian continent.

Alternative spelling of seasickness

A lake in the Middle East, noted for high salinity and for its banks being the lowest point on Earth.