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trimester

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noun tri·mes·ter \(ˌ)trī-ˈmes-tər, ˈtrī-ˌ\

Simple Definition of trimester

  • : a period of three months; especially : one of three periods into which a woman's pregnancy is often divided

  • : one of three periods into which an academic year is sometimes divided

Source: Merriam-Webster's Learner's Dictionary

Full Definition of trimester

  1. 1 :  a period of three or about three months; especially :  any of three periods of approximately three months each into which a human pregnancy is divided

  2. 2 :  one of three terms into which the academic year is sometimes divided

Examples of trimester in a sentence

  1. development in the first trimester



Did You Know?

Semester, which comes from the Latin words for "six" and "month", has come to mean half an academic year when the year is divided into two segments. When an academic year is divided into three segments, each is called a trimester (which is usually a bit more accurate, since each segment often is close to three months in length). Some colleges operate on the "quarter" system, with the summer being the fourth quarter, but this just means that each quarter is basically a trimester. In a human pregnancy, a trimester is three months long, representing one-third of the nine months that a typical pregnancy lasts.

Origin and Etymology of trimester

French trimestre, from Latin trimestris of three months, from tri- + mensis month — more at moon


First Known Use: 1821


Medical Dictionary

trimester

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noun tri·mes·ter \(ˈ)trī-ˈmes-tər, ˈtrī-ˌ\

Medical Definition of trimester

  1. :  a period of three or about three months; especially :  any of three periods of approximately three months each into which a human pregnancy is divided




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