Semi
/ˈsɛm.i/noun
A prefix meaning "half" or "partly."
Did you know?Semi- is from Latin *semi-* “half,” and it survived into English as a productive prefix in words like *semicircle* and *semifinal* rather than as a standalone word.
Etymological Timeline
Proto-Indo-European
PIE
*sm̥-
“half”
Latin
Latin
semi-
“half, partly”
Late Latin
Latin
semi-
“used as a prefix meaning half or partly”
Middle English
English
semi-
“a prefix meaning half or partly in learned borrowings”
Modern English
English
semi-
“a prefix meaning half or partly”
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