||Ac*tin"i*a (&?;), n.; pl. L. Actiniæ (&?;), E. Actinias (&?;). [Latinized fr. Gr. &?;, &?;, ray.] (Zoöl.) (a) An animal of the class Anthozoa, and family Actinidæ. From a resemblance to flowers in form and color, they are often called animal flowers and sea anemones. [See Polyp.]. (b) A genus in the family Actinidæ.
Ac*tin"ic (&?;), a. Of or pertaining to actinism; as, actinic rays.
Ac*tin"i*form (&?;), a. [Gr. &?;, &?;, ray + -form.] Having a radiated form, like a sea anemone.
Ac"tin*ism (&?;), n. [Gr. &?;, &?; ray.] The property of radiant energy (found chiefly in solar or electric light) by which chemical changes are produced, as in photography.
Ac*tin"i*um (&?;), n. [Gr. &?;, &?;, ray.] (Chem.) A supposed metal, said by Phipson to be contained in commercial zinc; -- so called because certain of its compounds are darkened by exposure to light.
Ac`ti*no-chem"is*try (&?;), n. Chemistry in its relations to actinism. Draper.
Ac*tin"o*graph (&?;), n. [Gr. &?;, &?;, ray + -graph.] An instrument for measuring and recording the variations in the actinic or chemical force of rays of light. Nichol.
Ac"tin*oid (&?;), a. [Gr. &?;, &?;, ray + -oid.] Having the form of rays; radiated, as an actinia.
Ac*tin"o*lite (&?;), n. [Gr. &?;, &?;, ray + -lite.] (Min.) A bright green variety of amphibole occurring usually in fibrous or columnar masses.
Ac`tin*o*lit"ic (&?;), a. (Min.) Of the nature of, or containing, actinolite.
Ac`ti*nol"o*gy (&?;), n. [Gr. &?;, &?;, ray + -logy.] The science which treats of rays of light, especially of the actinic or chemical rays.
Ac*tin"o*mere (&?;), n. [Gr. &?;, &?;, ray + &?; part.] (Zoöl.) One of the radial segments composing the body of one of the Cœlenterata.
Ac`ti*nom"e*ter (&?;), n. [Gr. &?;, &?;, ray + -meter] (a) An instrument for measuring the direct heating power of the sun's rays. (b) An instrument for measuring the actinic effect of rays of light.
Ac`ti*no*met"ric (&?;), a. Pertaining to the measurement of the intensity of the solar rays, either (a) heating, or (b) actinic.
Ac`ti*nom"e*try (&?;), n. 1. The measurement of the force of solar radiation. Maury.