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semi-
(SEM-ee)half
Latin for half. A semicircle is half a circle; a semifinal is the round before the final.
prefixLatin
Number & quantityExample words
semicircle
half of a circle
semifinal
the round before the final
semiannual
happening twice a year — every half year
Common Core alignment
Grades served: 4, 5
- L.4.4bUse common, grade-appropriate Greek and Latin affixes and roots as clues to the meaning of a word (e.g., telegraph, photograph, autograph).
- L.5.4bUse common, grade-appropriate Greek and Latin affixes and roots as clues to the meaning of a word (e.g., photograph, photosynthesis).
Number & quantity. Roots that count, measure, and tell you how many.
Browse all number & quantity roots →L.4.4bL.5.4b