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definitions

scalar

[skey-ler]
adjective
  1. representable by position on a scale or line; having only magnitude: a scalar variable.
  2. of, relating to, or utilizing a scalar.
  3. ladderlike in arrangement or organization; graduated: a scalar structure for promoting personnel.
noun
  1. Mathematics, Physics. a quantity possessing only magnitude.Compare vector(def 1a).

Origin of scalar

First recorded in 1650–60, scalar is from the Latin word scālāris of a ladder. See scale3, -ar1
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for scalar

scalar

noun
  1. a quantity, such as time or temperature, that has magnitude but not directionCompare vector (def. 1), tensor (def. 2), pseudoscalar, pseudovector
  2. maths an element of a field associated with a vector space
adjective
  1. having magnitude but not direction

Word Origin for scalar

C17 (meaning: resembling a ladder): from Latin scālāris, from scāla ladder
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 scalar
adj.

"resembling a ladder," 1650s, from Latin scalaris "of or pertaining to a ladder," from scalae (plural) "ladder, steps, flight of steps" (see scale (n.2)). Mathematical sense first recorded 1846.

Online Etymology Dictionary, © 2010 Douglas Harper
scalar in Science

scalar

[skā′lər]
  1. A quantity, such as mass, length, or speed, whose only property is magnitude; a number. Compare vector.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.