[ si-mes-ter ]
/ sɪˈmɛs tər /
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See synonyms for: semester / semestral on Thesaurus.com


(in many educational institutions) a division constituting half of the regular academic year, lasting typically from 15 to 18 weeks.
(in German universities) a session, lasting about six months and including periods of recess.



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Origin of semester

1820–30; <German <Latin sēmē(n)stris of six months duration <*sex-mēnstris, equivalent to sexsix + mēns(is) month + -tris adj. suffix (perhaps representing an earlier *mens(i)-teros)
se·mes·tral, se·mes·tri·al [si-mes-tree-uhl], /sɪˈmɛs tri əl/, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2021


What does semester mean?

A semester is one half of an academic year.

If an academic year is divided into semesters, it means it is divided into two semesters. (If the year is divided into thirds, each part is called a trimester.)

Semesters are typically used in high schools and universities. In many universities, a semester lasts 15 to 18 weeks. In German universities, a semester can last up to six months.

Example: I’m thinking about taking a break from school for a semester to work and save some money.

Where does semester come from?

The first records of the word semester come from the 1800s. It comes from the Latin sēmestris, meaning “half-yearly,” from sex, meaning “six,” and mensis, meaning “a month.”

In high school, many classes extend throughout both semesters, meaning students take that class throughout the entire academic year. But in college, new classes typically start each semester and end when the semester is over. Semesters typically run from August or September to December, and from January to May or June. When students take classes in the summer, it’s called the summer semester. Though many schools divide the academic year into semesters, others use a quarter or trimester system.

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What are some other forms related to semester?

  • semestral (adjective)
  • semestrial (adjective)

What are some synonyms for semester?

What are some words that share a root or word element with semester


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How is semester used in real life?

Semester is always used in the context of academic years—never for business schedules or other calendars.



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True or False?

If an academic year is divided into semesters, there are always two.

British Dictionary definitions for semester

/ (sɪˈmɛstə) /


(in some universities) either of two divisions of the academic year, ranging from 15 to 18 weeks
(in German universities) a session of six months
semestral, adjective
C19: via German from Latin sēmestris half-yearly, from sex six + mensis a month
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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