noun ·Rare ·Advanced level

Definitions

Noun

1. 1
   One who, or that which, hardens.

   "the hardener of hearts"

2. 2
   one that hardens, especially a substance added to varnish or paint to give it a harder surface or finish. wordnet
3. 3
   A chemical substance added to something in order to harden it; used especially with paints, varnishes and resins.

Etymology

From harden + -er.

Data sourced from Wiktionary, WordNet, CMU, and other open linguistic databases. Updated March 2026.