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Janus-faced

American  
[jey-nuhs-feyst] / ˈdʒeɪ nəsˌfeɪst /

adjective

  1. having two faces, one looking forward, one looking backward, as the Roman deity Janus.

  2. having two contrasting aspects, as the alternation of mood in a capricious person.

  3. two-faced; deceitful.

  4. aware of or concerned with polarities; seeing different and contrasting aspects.

    a Janus-faced view of history.

  5. having or containing contrasting characteristics.

    a Janus-faced policy.
Janus-faced British  

adjective

  1. two-faced; hypocritical; deceitful

"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 Janus-faced

First recorded in 1675–85; Janus ( def. ) + faced ( def. )

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.