D defs.my
Entry 1 sense Webster, 1913

Hardener

/(-'n*ẽr)/ · Hard·en·er · IPA /ˈhɑɹdn̩ɚ/
01 n. One who, or that which, hardens; specif., one who tempers tools.
  1. 1.
    One who, or that which, hardens; specif., one who tempers tools.