[foh-ton] /ˈfoʊ tɒn/
a quantum of electromagnetic radiation, usually considered as an elementary particle that is its own antiparticle and that has zero rest mass and charge and a spin of one. Symbol: γ.
a quantum of electromagnetic radiation, regarded as a particle with zero rest mass and charge, unit spin, and energy equal to the product of the frequency of the radiation and the Planck constant
“unit of electromagnetic radiation,” 1926 in modern sense, from photo- “light” + -on “unit.”
photon pho·ton (fō’tŏn’)
The quantum of electromagnetic energy, generally regarded as a discrete particle having zero mass, no electric charge, and an indefinitely long lifetime.
The subatomic particle that carries the electromagnetic force and is the quantum of electromagnetic radiation. The photon has a rest mass of zero, but has measurable momentum, exhibits deflection by a gravitational field, and can exert a force. It has no electric charge, has an indefinitely long lifetime, and is its own antiparticle. See Note at electromagnetic radiation. See Table at subatomic particle.
The quantum, or bundle of energy, in which light and other forms of electromagnetic radiation are emitted. (See atom.)
/ˈfəʊtəʊˌnæstɪ/ noun (pl) -ties 1. a nastic movement in response to a change in light intensity
[foh-tuh-neg-uh-tiv] /ˌfoʊ təˈnɛg ə tɪv/ adjective, Physics. 1. pertaining to a substance, as selenium, having a conductivity that decreases upon absorption of electromagnetic radiation. /ˌfəʊtəʊˈnɛɡətɪv/ adjective 1. (physics) (of a material) having an electrical conductivity that decreases with increasing illumination
[foh-tuh-noo-tron, -nyoo-] /ˌfoʊ təˈnu trɒn, -ˈnyu-/ noun, Physics. 1. a emitted from a nucleus during photodisintegration. /ˌfəʊtəʊˈnjuːtrɒn/ noun 1. a neutron emitted from a nucleus as a result of photodisintegration
[foh-ton-ik] /foʊˈtɒn ɪk/ adjective 1. of or relating to processes involving .