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
Cortne Bonilla, Vogue, 9 Oct. 2025
Omega-3s accumulate in the brain and retina of the eye during the third trimester of pregnancy.
—Brittany Lubeck, Verywell Health, 8 Oct. 2025
The actress, model and entrepreneur had progressed beyond the first trimester.
—Julio Cesar Valdera Morales, MSNBC Newsweek, 6 Oct. 2025
An expecting mother’s blood volume rises by 45% and even up to 50-60% percent in the late third trimester to feed the growing fetus.
—Elizabeth Yuko, Flow Space, 30 Sep. 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 30 Oct. 2025.
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trimester
noun
ˈtrī-ˌ
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