Origin of semi
- L < IE *semi- > Gr hēmi-, Sans sāmi-, OE sām-
From Webster's New World College Dictionary, 5th Edition
- Middle English from Latin sēmi- half sēmi- in Indo-European roots
From American Heritage Dictionary of the English Language, 5th Edition
- The prefix semi- (from Latin) used as a noun.
- From Latin semi- (“half").