menstruation

noun

men·​stru·​a·​tion ˌmen(t)-strü-ˈwā-shən 

men-ˈstrā-

: a cyclical discharging of blood, secretions, and tissue debris from the uterus that recurs in nonpregnant breeding-age primate females at approximately monthly intervals and that is considered to represent a readjustment of the uterus to the nonpregnant state following proliferative changes accompanying the preceding ovulation

also : period sense 6c

Synonyms of menstruation

• period

Examples of menstruation in a Sentence

a first menstruation can be somewhat scary for girls who are unprepared

Recent Examples on the Web

Participants using the OhmBody wearable daily during menstruation experienced an average reduction in menstrual blood loss of more than 50 percent and periods that were nearly 20 percent shorter. —Neetika Walter, Interesting Engineering, 7 Jan. 2026

In women, extreme deficits can cause irregular periods or even amenorrhea (loss of menstruation). —Heather Jones, Verywell Health, 6 Jan. 2026

These injuries resulted in 684 days lost per 1,000 training hours during menstruation, compared to 206 days lost during non-bleeding days. —Ciara Lucas, SELF, 16 Dec. 2025

Menstrual Cramps and Bleeding Uterine cramping and bleeding is a normal part of menstruation, but some people have unusually painful periods or excessive bleeding. —Sarah Bradley, Health, 11 Dec. 2025

Word History

First Known Use

1686, in the meaning defined above

Rhymes for menstruation

• abdication
• aberration
• abjuration
• abnegation
• abrogation
• acceptation
• acclamation
• acclimation
• accusation
• activation
• actuation
• acylation

Kids Definition

menstruation

noun

men·​stru·​a·​tion ˌmen(t)-strə-ˈwā-shən 

men-ˈstrā-shən

: a discharging of blood, secretions, and tissue debris from the uterus at periods of approximately one month in female primates of breeding age that are not pregnant

also : period sense 3c

Medical Definition

menstruation

noun

men·​stru·​a·​tion ˌmen(t)-strə-ˈwā-shən, men-ˈstrā- 

: a discharging of blood, secretions, and tissue debris from the uterus that recurs in nonpregnant human and other primate females of breeding age at approximately monthly intervals and that is considered to represent a readjustment of the uterus to the nonpregnant state following proliferative changes accompanying the preceding ovulation

also : period sense 1b