Where does “Dennis” come from?

Dennis (English) comes from Middle English Denis, from Old French Denis, from Latin Dionȳsius, from Ancient Greek Διονύσιος, from Ancient Greek -ῐος, from Proto-Indo-European -yós — Creates adjectives from noun or verb stems.

Ancestry of “Dennis”, step by step

StepLanguageWordMeaning
1Middle EnglishDenis—
2Old FrenchDenis—
3LatinDionȳsiustyrant of Syracuse
4Ancient GreekΔιονύσιος—
5Ancient Greek-ῐοςbelonging to; of”, “belonging to”, “pertaining to
6Proto-Indo-European-yósCreates adjectives from noun or verb stems

Words derived from “Dennis”

Every word from Proto-Indo-European -yós →Every word from Ancient Greek -ῐος →Every word from Ancient Greek Διονύσιος →