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
Julia Ries Wexler, SELF, 9 Feb. 2026
Across the state, cases of sepsis in second-trimester pregnancy losses shot up more than 50% after the ban took effect, according to a data analysis by ProPublica.
—Cassandra Jaramillo, CNN Money, 9 Feb. 2026
Often, testing is repeated during the third trimester and then when you are admitted to the hospital before giving birth.
—wendy Wisner, Parents, 4 Feb. 2026
Cassandra King was thrilled to complete the first trimester of her pregnancy in the fall of 2024.
—Kerry Breen, CBS News, 24 Jan. 2026
See All Example Sentences for trimester
Cite this Entry
“Trimester.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/trimester. Accessed 15 Feb. 2026.
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trimester
noun
ˈtrī-ˌ
