trimester
trimester
Noun
pl: trimesters
This term is most frequently encountered in medical contexts to divide the forty weeks of human pregnancy into three distinct developmental stages. Each stage marks a shift in fetal growth and maternal experience, moving from organogenesis in the first to rapid growth and viability in the third.
In academic settings, it describes a specific calendar division of the school year. While a semester divides the year into two parts, a trimester splits it into three, often resulting in shorter, more intensive periods of study.