antiparallel

[ an-tee-par-uh-lel, an-tahy- ]
/ ˌæn tiˈpær əˌlɛl, ˌæn taɪ- /

adjective Mathematics, Physics.

(of two vectors) pointing in opposite directions.

Origin of antiparallel

First recorded in 1650–60; anti- + parallel
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for antiparallel

antiparallel

/ (ˌæntɪˈpærəˌlɛl) /

adjective

physics parallel but pointing in the opposite direction
maths (of vectors) parallel but having opposite directions
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