• synonyms


[uh b-zur-vuh-buh l]
See more synonyms for observable on Thesaurus.com
  1. capable of being or liable to be observed; noticeable; visible; discernible: an observable change in attitude.
  2. worthy or important enough to be celebrated, followed, or observed: an observable holiday.
  3. deserving of attention; noteworthy.
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Origin of observable

1600–10; < Latin observābilis remarkable, equivalent to observā(re) to observe + -bilis -ble
Related formsob·serv·a·bil·i·ty, ob·serv·a·ble·ness, nounob·serv·a·bly, adverbnon·ob·serv·a·ble, adjectivenon·ob·serv·a·bly, adverbun·ob·serv·a·ble, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

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Examples from the Web for observable

Contemporary Examples

Historical Examples

  • Between the "wondering" and the noun there had been an observable pause.

  • On the 15th of September, 17—, an unusual stir was observable in our village.

  • The only other observable symptom was slightly increased thirst.

    Pariah Planet

    Murray Leinster

  • It is observable that he does not absolutely deny that there is an opposite of Being.



  • A tendency to a paradoxical manner of statement is also observable.



Word Origin and History for observable


c.1600, from Latin observabilis "remarkable, observable," from observare (see observe). Related: Observably; observability.

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Online Etymology Dictionary, © 2010 Douglas Harper

observable in Science


  1. A measurable property of a physical system, such as mass or momentum. In quantum mechanics, observables correspond to mathematical operators used in the calculation of measurable quantities. Operators that do not commute, having a nonzero commutator, correspond to observables that cannot be precisely measured at the same time, such as momentum and position. See also uncertainty principle.
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The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.