- an interval of the menstrual cycle when fertilization is considered to be least likely, usually a number of days prior and subsequent to the onset of menstruation.
Origin of safe period
First recorded in 1915–20
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
- informal the period during the menstrual cycle when conception is considered least likely to occurSee also rhythm method
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
- The period in the menstrual cycle when conception is least likely, typically from ten days before to ten days after the onset of menstruation.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.