of or relating to a geometric plane.
flat or level.

Origin of planar

1840–50; < Late Latin plānāris flat, of a level surface, equivalent to Latin plān(um) plane1 + -āris -ar1
Related formspla·nar·i·ty [pluh-nair-i-tee] /pləˈnɛər ɪ ti/, noun Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for planar



of or relating to a plane
lying in one plane; flat
Derived Formsplanarity (pleɪˈnærɪtɪ), noun

Word Origin for planar

C19: from Late Latin plānāris on level ground, from Latin plānus flat
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 planar

1850, from Latin planaris "level, flat," from planum "plane" (see plane (n.1)).

Online Etymology Dictionary, © 2010 Douglas Harper