English
hardenable
From harden + -able.
Formed from harden + -able
Proto-Germanic *harduz ‘hard’
…
Proto-West Germanic *hardēn ‘to become hard, harden, solidify’
Old English heardian ‘to be or become hard’
Middle English harden
Middle English hardenen
English harden
Today it means
adj Capable of being hardened.
Language periods are conventional ranges, not dates for this word.
Etymograph / hardenable