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definitions

countable

[koun-tuh-buh l]
adjective
  1. able to be counted.
  2. Mathematics.
    1. (of a set) having a finite number of elements.
    2. (of a set) having elements that form a one-to-one correspondence with the natural numbers; denumerable; enumerable.

Origin of countable

1400–50; late Middle English. See count1, -able
Related formscount·a·bil·i·ty, count·a·ble·ness, nouncount·a·bly, adverb
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for countability

countable

adjective
  1. capable of being counted
  2. maths logic able to be counted using the natural numbers; finite or denumerable
  3. linguistics denoting a count noun
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