Where does “firma” come from?
firma (Classical Nahuatl) comes from Spanish firma, from Spanish firmar, from Latin firmō, from Latin Firmus, from Proto-Italic fermos, from Proto-Indo-European dʰer-mo-s, from Proto-Indo-European dʰer- — to support; to hold.
firma (Classical Nahuatl): A signature
Ancestry of “firma”, step by step