verb (used with object), un·ion·ized, un·ion·iz·ing.

to form into a union.
to organize into a labor union; bring into or incorporate in a labor union.
to subject to the rules of a labor union.

verb (used without object), un·ion·ized, un·ion·iz·ing.

to form a union.
to join in a labor union.

Also especially British, un·ion·ise.

Origin of unionize

First recorded in 1835–45; union + -ize
Related formsun·ion·i·za·tion, nounun·ion·iz·er, nouno·ver·un·ion·ize, verb, o·ver·un·ion·ized, o·ver·un·ion·iz·ing.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for unionization

Contemporary Examples of unionization

Historical Examples of unionization

  • Did Mr. Kane promise to grant every demand, except only unionization?


    Clement Wood

  • The company had refused to accede to the demands for unionization, even with a waiver of all other claims.


    Clement Wood

  • They agree to consider every one of our demands, provided only we don't insist on the demand for unionization.


    Clement Wood

  • It was a lost opportunity that unquestionably cost the unionization of the steel industry.

  • These locals, therefore, have been a great obstacle to the unionization of Negroes.

British Dictionary definitions for unionization




to organize (workers) into a trade union
to join or cause to join a trade union
(tr) to subject to the rules or codes of a trade union
to join or become joined in marriage or civil partnership
Derived Formsunionization or unionisation, 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

Word Origin and History for unionization



"make into a union," 1841, from union + -ize. Related: Unionized; unionizing.

Online Etymology Dictionary, © 2010 Douglas Harper