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[yoo-ni-di-rek-shuh-nl, -dahy-] /ˌyu nɪ dɪˈrɛk ʃə nl, -daɪ-/
operating or moving in one direction only; not changing direction:
a unidirectional flow.
Origin of unidirectional
1880-85; uni- + directional Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
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Examples from the web for unidirectional
  • It's fair to say that so-called unidirectional amplifiers have had a profound impact on our society.
  • Clearly it is unidirectional, which makes it different than the others.
  • Most models of anticipation take for granted that events unfold in a unidirectional flow of time, from past to future.
  • When returns are in the walls, there are restrictions as to how wide the room can be and still maintain unidirectional flow.
  • A unidirectional microphone is sensitive to sounds from only one direction.
British Dictionary definitions for unidirectional


/ˌjuːnɪdɪˈrɛkʃənəl; -daɪ-/
having, moving in, or operating in only one direction
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
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Word Origin and History for unidirectional

1883, from uni- + directional (see direction).

Online Etymology Dictionary, © 2010 Douglas Harper
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