[ hahr-dn-er ]
/ ˈhɑr dn ər /
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a person or thing that hardens.
a substance mixed with paint or other protective covering to make the finish harder or more durable.
Photography. a chemical used to raise the melting point of an emulsion.



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“Was” is used for the indicative past tense of “to be,” and “were” is only used for the subjunctive past tense.

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Origin of hardener

First recorded in 1605–15; harden + -er1
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2021

Example sentences from the Web for hardener

  • Guet and guiv demand dhe (u) hardener, az boldly az gues and guilt.

  • A recent rival of tungsten both as a filament for lamps and hardener for steel is molybdenum.

    Creative Chemistry|Edwin E. Slosson
  • They are so cruel, without even knowing that they are so: the habit of seeing sin and suffering is such a heart-hardener.

    Records of Later Life|Frances Ann Kemble
  • She was a harmful woman, a destroyer of young tempers, a hardener of young hearts.

    Stage Confidences|Clara Morris

British Dictionary definitions for hardener

/ (ˈhɑːdə) /


a person or thing that hardens
a substance added to paint or varnish to increase durability
an ingredient of certain adhesives and synthetic resins that accelerates or promotes setting
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