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antiparallel

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

adjective

Mathematics, Physics.

  1. (of two vectors) pointing in opposite directions.

antiparallel British  
/ ˌæntɪˈpærəˌlɛl /

adjective

  1. physics parallel but pointing in the opposite direction

  2. 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

Etymology

Origin of antiparallel

First recorded in 1650–60; anti- + parallel

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.