[trans-mit-ns, tranz-]


Physics. the ratio of the radiant flux transmitted through and emerging from a body to the total flux incident on it: equivalent to one minus the absorptance.

Origin of transmittance

First recorded in 1850–55; transmit + -ance
Also called transmission.
Related formsnon·trans·mit·tance, noun Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for transmittance

Historical Examples of transmittance

  • Music fills all which contains life, and uses all materials for its transmittance.

    Seed Thoughts for Singers

    Frank Herbert Tubbs

British Dictionary definitions for transmittance



the act of transmitting
Also called: transmission factor physics a measure of the ability of anything to transmit radiation, equal to the ratio of the transmitted flux to the incident flux; the reciprocal of the opacity. For a plate of material the ratio of the flux leaving the entry surface to that reaching the exit surface is the internal transmittanceSymbol: τ Compare reflectance, absorptance
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for transmittance

1855, from transmit + -ance.

Online Etymology Dictionary, © 2010 Douglas Harper