(a) A boundary between kingdoms, estates, fields, etc.; the outer limits of a country, a military encampment, etc.; bounds set for creatures, the sea, water, etc.; also, the land along the boundary……
(a) A lake, pond, pool; also, a sea or an ocean [quots.: Cleanness, Patience, Bokenham]; (b) mere grot [OE], ?a pearl, ?a pebble; mere grote-ston, a pearl; mere naddre [OE merenǣddra], a lamprey……
