Lacuna

la-ku'na, n. pi. -ne. A small opening, pit, or depre ion; blank space; vacancy; niatus. (Bot.) The small pit or cup-shaped depre ion in the top of the thallus of some lichens; a vacant space between the cells of plants; an air-cell. (Anat.) A small cavity or sac in a mucous membrane. [L.; Gr. tokos, a hole, pit, tank: see Lake, water.] Lacustral, Lacustrine. See under Lake. uad, lad, n. A young man, or boy; stripling; fellow; Comrade. [W. llawd, Ir. lath, a youth, Ir. and Ga. tuth, strength; la .] T.ajjftnnm, lad'a-num, n. A gum-resin of a dark color and pungent odor, chiefly used as an external stimulant. [L. See Laudanum.]