actino-, actin-, actini-, -actinal, actis- +

(Greek: ray [as of light] or like a ray in form; radiance, radiation; a radiating or tentacled structure)

actinopraxis (s), actinopraxes (pl) (nouns)
A former term for radiology or the taking of X-rays: "Medical technicians once used an actinopraxis to make radiation examinations."
A fish that has fan-shaped fins supported by radiating spines or rays.

Nearly all living bony fishes are actinopterygians.

A subclass of bony fishes often called ray-finned fish, consisting of many extinct groups and most living bony fish, having ganoid scales (a type of scale consisting of dentine-covered bone with a thick outer layer of a substance similar to enamel) and usually paired fins with broad bases.
A symbiotic association between certain plant roots and certain bacteria, such as Frankia strains (nitrogen-fixing root-nodule symbionts of many species of woody dicotyledonous plants), in which nitrogen fixation occurs within specialized root nodules.
A former term for fluoroscopy or an X-ray machine that combines an X-ray source and a fluorescent screen to enable direct observation.
A former term for radiostereoscopy or the simultaneous viewing of two radiographs (X-rays) made in slightly different projections, usually with a device that reflects the image of one on each eye, allowing three-dimensional visualization of an object in relation to others.
The mouth of a radially symmetrical animal; such as, the starfish.
The use of rays of light, particularly ultraviolet, for the treatment of diseases that are at or near the surface of the body.
1. The treatment of a disease with ultraviolet or actinic rays.
2. Treatment of a disease with rays of light; especially actinic or photochemically active rays, X-rays, radium, and other radio-chemicals.
A term for radiation sickness.
A crude poison derived from alcoholic extracts of the tentacles of sea anemones.
1. Threadlike (hairlike) fibers in the finfolds of fish larvae that eventually develop into fin rays.
2. Slender, horny, flexible, unsegmented fibrils which strengthen the embryonic fin fold or the unjointed horny rays at the edge of fins in many fish.

Actinotrichia are translucent, exhibit birefringence (double refraction) and are composed of a scleroprotein called elastoidine.

The former name of the radioactive uranium isotope of mass 235 that is now called uranium-235.
actinozoa, anthozoa
Solitary or colonial coelenterates without any free-swimming medusa stage and with the coelenteron divided by mesenteries.

The group includes most of the common sea-anemones and corals.

Coelenterata consist of a rather large phylum of sedentary or free-swimming animals having a radially symmetrical sac-like body with a mouth at one end, usually surrounded by a ring of stinging tentacles.

The digestive cavity, known as the coelenteron, has only this opening, but repeated budding may give rise to a colony in which all the body-cavities are connected with each other.

The body-wall is diploblastic, that is, made of two layers of cells, ectoderm and endoderm with a gelatinous layer known as the mesogloea between them.

The individuals of a colony are known as polyps or hydroids. They form the asexual sedentary generation which alternates with a free-swimming sexual phase known as the medusa. The latter is a disc-shaped jelly-fish which breaks away from the parent colony and swims away. It produces gametes and after fertilization has taken place, a new polyp colony develops.

Included in the Coelenterata are corals and anemones in which the hydroid stage is dominant, jelly-fish in which the medusoid stage is dominant, and complex forms such as the Portuguese Man-of-war formed by a large floating colony of diverse polyps.

—A.W. Leftwich, A Dictionary of Zoology;
Crane Russak & Company; New York; 1964.
Of or pertaining to the Actinozoa.