trimester
noun
ˈtrī-ˌme-
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.
Examples of trimester in a Sentence
Anuradha Varanasi, Forbes.com, 23 July 2025
Two first trimesters back to back with no baby to show for it is a personal hell.
—Daniella Gray, MSNBC Newsweek, 18 July 2025
Such links were particularly pronounced when exposure occurred during the month before conception and during the first trimester of pregnancy, researchers reported in the study, published in Environmental Science & Technology.
—Sharon Udasin, The Hill, 23 June 2025
Hormonal changes are responsible for triggering things like nausea and dizziness, including that pesky morning sickness, particularly in the first trimester.
—Rachel Nall, SELF, 17 June 2025
See All Example Sentences for trimester
Cite this Entry
“Trimester.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/trimester. Accessed 29 Jul. 2025.
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trimester
noun
ˈtrī-ˌ
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