hardener

== English == === Etymology === From harden +‎ -er. === Pronunciation === (US) IPA(key): /ˈhɑɹdn̩ɚ/, /ˈhɑɹdənɚ/ (UK) IPA(key): /ˈhɑːdn̩ə/, /ˈhɑːdənə/ === Noun === hardener (plural hardeners) One who, or that which, hardens. the hardener of hearts A chemical substance added to something in order to harden it; used especially with paints, varnishes and resins. === Anagrams === reharden