Semester

An academic term (or simply "term") is a portion of an academic year, the time during which an educational institution holds classes. The schedules adopted vary widely.

The word quadmester or quadrimester is occasionally used to mean either four months or (more commonly in modern American usage) a quarter of a year. In countries like Argentina, public universities divide the academic year into two quadrimesters (March–July and August–December).

In most countries, the academic year begins in late summer or early autumn and ends during the following spring or summer. In Northern Hemisphere countries, this means that the academic year lasts from August, September, or October to May, June, or July. In Southern Hemisphere countries, the academic year aligns with the calendar year, lasting from February or March to November or December. The summer may or may not be part of the term system.

A "semester" (from the Latin meaning "six-monthly") has come to mean either of two academic terms, generally excluding the summer or January terms, if any, and so can be 12 to 20 weeks long. The word "semester" is sometimes used as a synonym for a "term", as in a "summer semester".

A "trimester" (from the Latin meaning "three-monthly") divides the academic year into three periods, separated by breaks. In some jurisdictions, "trimester" is used in its original meaning to indicate a quarter system (since three months is exactly a quarter of a year), or a variation of it.

A "quarter" system treats the summer term on an equal footing with the other terms. It divides the academic year into four quarters, each of which is usually 12 weeks long. Three of the four quarters (Autumn/Fall, Winter, and Spring, operating from September until June or from August until May) are thus equivalent to two 18-week semesters. Thus, when American academic universities convert academic credits between the semester/trimester and quarter systems, 36 quarter hours convert to 24 semester hours (⅔ conversion factor) while 36 semester hours convert to 54 quarter hours (3/2 conversion factor). The rare word quadmester or quadrimester is occasionally used for either a three-term system or a four-term system.

In most of Australia, the primary and secondary school year lasts approximately 200 days, from late January or early February to early or mid-December, and is split into four terms:

Terms 4&1 (rolled over) and 2&3 are respectively usually deemed 'summer' and 'winter' respectively for purposes of sports participation and uniform standards. Australian states and territories vary their approach to Easter when determining the dates for the holiday at the end of Term 1.

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