sesqui-

1. a combining form meaning “one and a half,” used in the formation of compound words.

   sesquicentennial.

sesqui-

prefix

1. indicating one and a half

   sesquicentennial

2. (in a chemical compound) indicating a ratio of two to three

   sesquioxide

Word History and Origins

Origin of sesqui-¹

< Latin sēsqui- < *sēm ( i ) sque, equivalent to sēmis half-unit, semis + -que and (cognate with Greek té, Sanskrit ca, Gothic -uh )

Word History and Origins

Origin of sesqui-¹

from Latin, contraction of _semi- + as _as ² + -que and

Example Sentences

In 1961, a group of Black protesters, most of them local college students, attempted to the enter Sesqui, which was open to White visitors only.

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He has memories from growing up of visiting the park with family, but he never knew “Sesqui” had a campground.

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On a cool November morning - prime hiking weather - Hunter walked the trails of Sesqui with state parks Director Paul McCormack, discussing what’s become their shared mission: making state park campgrounds look more like the communities they serve.

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Its name: the Sesquicentennial Amphitheater, “Sesqui” for short.

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Sesqui-, Latin for one and a half; so Sesquipedalis, a foot and a half long.

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When To Use

What does sesqui- mean?

Sesqui- is a combining form used like a prefix meaning "one and a half." It is occasionally used in scientific terms, especially in chemistry.Sesqui- comes from Latin and is equivalent to sēmis, meaning "half-unit," and -que, a suffix meaning "and." The Greek cognate of sēmis is hēmi-, meaning "half," which is the source of terms such as hemisphere. To learn more, check out our Words That Use article on the combining form hemi-.