Where does “endurecer” come from?
endurecer (Spanish) comes from Latin indūrēscere, from Latin induro, from Latin dūrō, from Latin dūrus, from Proto-Italic dūros, from Proto-Indo-European duh₂-ró-s, from Proto-Indo-European dweh₂- — far; long.
endurecer (Spanish): to harden, make hard
Ancestry of “endurecer”, step by step