a combining form with the meaning “ray, beam,” used in the formation of compound words, with the particular senses “radiation” in the physical sciences (actinometer) and “having raylike structures,” “radiate in form” in biology (actinomyces; actinopod).
indicating a radial structure: actinomorphic
indicating radioactivity or radiation: actinometer
before vowels actin-, word-forming element meaning “pertaining to rays,” from Greek aktis (genitive aktinos) “ray, radiance;” perhaps cognate with Sanskrit aktuh “light, ray,” Gothic uhtwo “dawn, daybreak,” Lithuanian anksti “early.”
actino- or actin-
Actinic radiation: actinotherapy.
any of several spherical or rod-shaped, aerobic, parasitic bacteria of the genus Actinobacillus, certain species of which, as A. mallei, are pathogenic for animals.
an infectious disease of cattle, domestic animals, and occasionally humans, resembling actinomycosis and caused by the bacterium Actinobacillus lignieresii. noun (vet science) a disease of cattle and sheep, caused by infection with an Actinobacillus lignieresii and characterized by soft tissue lesions, esp of the tongue Also called wooden tongue, woody tongue, cruels
the branch of dealing with actinism; photochemistry. noun another name for photochemistry
noun the branch of biology concerned with the effects of radiation on living organisms