Midterm

wiktionary

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mid- +‎  term

etymonline

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midterm (adj.)

also mid-term, "in the middle of a term" in any sense, from mid (adj.) + term (n.). By 1879 in reference to gestation; 1888 of college semesters (midterm examination is by 1900; student slang shortening midterms for these is by 1903). By 1891 in reference to U.S. congressional elections held in the middle of a four-year presidential term.