Any of various sacs or pouch-like cavities in the body of an animal or in a plant. Now chiefly Zoology.

= cyst, n.

A bladder-like vessel or formation; a vesicle.

Anatomy and Zoology. A small bladder-like vessel in an animal body; a cavity or cell with a membranous integument; a small sac or cyst.

An internal cavity. Obsolete.

Any small hollow or cavity in an animal body, serving as a place of organic function; in later use, the recess or space between the true and false…

= vesicle, n. 1. Usually in plural.

Medicine. An abnormal or artificially created structure or space in the body that resembles a bag or pocket; an aneurysm, a cyst (now rare); a sac…

Biology. A thin-walled hollow organ or cavity in an animal body (or plant) containing a liquid secretion; a bladder, sac, vesicle.

Biology. Any natural bag-like cavity with its membranous covering in an animal or vegetable organism. in animal bodies. laryngeal sacs…

Zoology. A thin, flat, leaflike structure; esp. a gill filament in a fish or aquatic invertebrate (cf. gill leaf n. at gill, n.1 compounds 3).

Physiology and Biology. Variant spelling of calix, n.

Anatomy. A small, usually rounded structure or organ; spec. = lymph node n. at lymph, n. compounds 3.