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From Proto-Slavic *-inъ.
From Latin -īnus, from Proto-Indo-European *-iHnos.
From Middle High German -inne, -in, from Old High German -inna, from Proto-Germanic *-injō. Cognate with Dutch -in, Swedish -inna.
From Middle High German -inne, -in, -īn. Compare German -in.
From Arabic ين (-īn), oblique case form of ون (-ūn), masculine personal plural suffix.
From Old Dutch *-īn, from Proto-Germanic *-īnaz.
From Proto-Samic *-jnē, originally the essive case of a possessive adjective in *-j-.
Old High German
From Proto-Germanic *-īnaz.
From Proto-Brythonic *-in, from Proto-Celtic *-īnos, from Proto-Indo-European *-iHnos.