a dielectric that possesses a permanent or semipermanent electric polarity, analogous to a permanent magnet.
Origin of electret
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
a permanently polarized dielectric material; its electric field is similar to the magnetic field of a permanent magnet
Word Origin for electret
C20: from electr (icity + magn) et
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