ACTINULA
Ac*tin"u*la, n. pl. Etym: [NL., fr. Gr. (Zoöl.)

Defn: A kind of embryo of certain hydroids (Tubularia), having a stellate form.

ACTION
Ac"tion, n. Etym: [OF. action, L. actio, fr. agere to do. See Act.]

1. A process or condition of acting or moving, as opposed to rest; the doing of something; exertion of power or force, as when one body acts on another; the effect of power exerted on one body by another; agency; activity; operation; as, the action of heat; a man of action. One wise in council, one in action brave. Pope.

2. An act; a thing done; a deed; an enterprise. (pl.): Habitual deeds; hence, conduct; behavior; demeanor. The Lord is a Good of knowledge, and by him actions are weighed. 1 Sam. ii. 3.

3. The event or connected series of events, either real or imaginary, forming the subject of a play, poem, or other composition; the unfolding of the drama of events.

4. Movement; as, the horse has a spirited action.

5. (Mech.)

Defn: Effective motion; also, mechanism; as, the breech action of a gun.

6. (Physiol.)