quantum bit


the fundamental unit of information in a quantum computer, capable of existing in two states, 0 or 1, simultaneously or at a different time.

Nearby words

  1. quantometer,
  2. quantong,
  3. quantrill,
  4. quantrill, william clarke,
  5. quantum,
  6. quantum chemistry,
  7. quantum chromodynamics,
  8. quantum computer,
  9. quantum cryptography,
  10. quantum efficiency

Also called qu·bit [kyoo-bit] /ˈkyuˌbɪt/.

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for qubit


/ (ˈkjuːbɪt) /


computing a quantum bit

Word Origin for qubit

C20: from qu (antum) + bit 4

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

Science definitions for qubit


[ kyōōbĭt′ ]

See quantum bit.

quantum bit

The smallest unit of information in a quantum computer. Unlike bits in classical systems, which are in one of two possible states labelled 1 and 0, a quantum bit exists in a superposition of these two states, settling on one or the other only when a measurement of the state is made. Also called qubit
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