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a bacterium of the order Actinomycetales.
ray fungus(1) A nonspecific term for any fungus-like bacterium of the order Actinomycetales.
a line emanating from a center, as a more or less distinct portion of radiant energy (light or heat), proceeding in a specific direction.
α-r's high-speed helium nuclei ejected from radioactive substances; they have less penetrating power than beta rays. See also alpha particles.
β-r's, beta particles electrons ejected from radioactive substances with velocities as high as 0.98 of the velocity of light; they have more penetrating power than alpha rays, but less than gamma rays.
a digit of the hand or foot and corresponding metacarpal or metatarsal bone, regarded as a continuous unit.
branched filamentous appearance of Actinomyces bovis in granules in pus.
γ-r's electromagnetic radiation of short wavelengths emitted by an atomic nucleus during a nuclear reaction, consisting of high-energy photons, having no mass and no electric charge, and traveling with the speed of light and with great penetrating power.
a cortical extension of a bundle of tubules from a renal pyramid.