See Also: plasma(1)(dictionary)
plasma-(2)(dictionary)
plasma(encyclopedia)
Plasma(medicine)
plasma(dictionary)
Plasma(health)
plasma containment(medicine)
plasma cell(medicine)
plasma exchange(medicine)
plasma substitute(medicine)

plasma(1) (iou)



plasma noun. E18.
[Late Latin from Greek plasma, plasmat- mould, image, (also) formation, from plassein to mould, to form. Cf. PLASTIC adjective.]
Form, mould, shape. rare. E18-E19.
A subtranslucent green variety of chalcedony, valued as a semiprecious stone. L18.
Physiology. The pale yellowish protein-rich liquid in which the cells of the blood are suspended. Also, (the liquid component of) lymph. Freq. attrib. with ref. to (the concentration of) substances dissolved in the blood, as plasma protein. M19.
Biology. Protoplasm, cytoplasm. Now rare. M19.
Physics. An ionized gas containing electrons and free positive ions, formed usu. at high temperatures; esp. an electrically neutral one exhibiting certain phenomena due to the collective interaction of charges. Also, an analogous collection of charged particles in which one or both kinds are mobile, as the conduction electrons in a metal, the ions in a salt solution. E20.
Soil Science. The colloidal or relatively soluble material between grains of a soil. M20.
Comb. (see also PLASMA-): plasma arc a very hot plasma jet produced by passing a noble gas through a nozzle that is one electrode of an electric arc, used in plasma torches; plasma cell Physiology (a) a type of cell found in connective tissue; (b) a fully differentiated lymphocyte, a plasmacyte; plasma diagnostics Physics the determination of the characteristics of gaseous plasmas by methods which do not significantly alter them; plasma-dynamic, plasma-dynamical adjectives of or pertaining to plasma dynamics; plasma dynamics the branch of physics that deals with the dynamical properties and behaviour of gaseous plasmas; plasma engine a jet engine that produces and ejects gaseous plasma; plasma frequency the natural resonant frequency of a plasma oscillation, equal to the minimum frequency of electromagnetic waves that can travel through the plasma without attenuation; plasma jet a high-speed stream of plasma (ionized gas) ejected from a plasma engine or plasma torch; plasma membrane Biology a membrane which forms the external boundary of the cytoplasm of a cell or encloses a vacuole and regulates the passage of molecules in and out of the cytoplasm; plasma oscillation a collective oscillation of the charged particles in a plasma; plasma probe a device that is inserted or immersed in an ionized gas to investigate its physical properties; plasma propulsion: by means of a plasma engine; plasma sheath a thin charged layer covering a surface in an ionized gas; plasma sheet a layer of plasma in the earth's magnetotail, lying in the equatorial plane beyond the plasmapause, with two divergent branches that reach the earth in polar latitudes; plasma torch a small device that produces a very hot plasma jet for use in cutting solids or coating them with refractory material.