[ nuhl ]
See synonyms for null on
  1. without value, effect, consequence, or significance.

  2. being or amounting to nothing; nil; lacking; nonexistent.

  1. Mathematics. (of a set)

  2. being or amounting to zero.

  1. Electronics. a point of minimum signal reception, as on a radio direction finder or other electronic meter.

verb (used with object)
  1. to cancel; make null.

Idioms about null

  1. null and void, without legal force or effect; not valid: This contract is null and void.

Origin of null

1555–65; <Latin nūllus, equivalent to n(e) not + ūllus any

Words Nearby null Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use null in a sentence

British Dictionary definitions for null


/ (nʌl) /

  1. without legal force; invalid; (esp in the phrase null and void)

  2. without value or consequence; useless

  1. lacking distinction; characterless: a null expression

  2. nonexistent; amounting to nothing

  3. maths

    • quantitatively zero

    • relating to zero

    • (of a set) having no members

    • (of a sequence) having zero as a limit

  4. physics involving measurement in which an instrument has a zero reading, as with a Wheatstone bridge

Origin of null

C16: from Latin nullus none, from ne not + ullus any

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

Scientific definitions for null


[ nŭl ]

  1. Of or relating to a set having no members or to zero magnitude.

The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.