Di`a*ther"mal (?), a. [Gr. &?; thoroughly warm; dia` through + &?; warm, hot. Cf. Diathermous.] Freely permeable by radiant heat.
{ Di`a*ther"man*cy (?), Di`a*ther`ma*ne"i*ty (?), } n. [See Diathermanous.] The property of transmitting radiant heat; the quality of being diathermous. Melloni.
Di`a*ther"ma*nism (?), n. The doctrine or the phenomena of the transmission of radiant heat. Nichol.
Di`a*ther"ma*nous (?), a. [Gr. &?; to warm through; dia` through + &?; to warm, &?; warm.] Having the property of transmitting radiant heat; diathermal; -- opposed to athermanous.
Di`a*ther"mic (?), a. Affording a free passage to heat; as, diathermic substances. Melloni.
Di`a*ther*mom"e*ter (?), n. [Gr. &?; warm + -meter. See Diathermal.] (Physics) An instrument for examining the thermal resistance or heat- conducting power of liquids.
Di`a*ther"mous (?), a. Same as Diathermal.
||Di*ath"e*sis (?), n. [NL., fr. Gr. &?;, fr. &?; to place separately, arrange; dia` through, asunder + &?; to place, put.] (Med.) Bodily condition or constitution, esp. a morbid habit which predisposes to a particular disease, or class of diseases.
Di`a*thet"ic (?), a. Pertaining to, or dependent on, a diathesis or special constitution of the body; as, diathetic disease.
Di"a*tom (d`*tm), n. [Gr. dia`tomos cut in two. See Diatomous.] 1. (Bot.) One of the Diatomaceæ, a family of minute unicellular Algæ having a siliceous covering of great delicacy, each individual multiplying by spontaneous division. By some authors diatoms are called Bacillariæ, but this word is not in general use.