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signor vs. signer

signor
[seen-yawr, -yohr, sin-yawr, -yohr, see-nyawr] / ˈsin jɔr, -joʊr, sɪnˈjɔr, -ˈjoʊr, siˈnjɔr /
Also signior

noun

signors, plural signori plural

  1. a conventional Italian term of address or title of respect for a man, either used separately or prefixed to the name. Sig., sig.

signer
[sahy-ner] / ˈsaɪ nər /

noun

signers plural

  1. a person who signs.

  2. a person who writes their name, as in token of agreement.

  3. a person who communicates by or interprets into sign language.