- a period or term of three months; specif., any of the three three-month periods of a human pregnancy
- in some colleges and universities, any of the three periods into which the academic year is divided
Origin of trimesterFrench trimestre from Classical Latin trimestris, of three months from tri-, three + mensis, month: see moon
- A period or term of three months.
- One of three terms into which an academic year is divided in some universities and colleges.
Origin of trimesterFrench trimestre from Latin trimēstris, trimēnstris of three months tri- tri- mēnsis month ; see mē-2 in Indo-European roots.
- tri·mes′tral tri·mes′tri·al
- A period of three months or about three months.
- She is in the second trimester of her first pregnancy.
- One of the terms of an academic year in those learning institutions that divide their teaching in three roughly equal terms, each about three months long. Compare semester.
- The school operates on a trimester schedule.