(n)natural family planning in which the fertile period is inferred from changes in the character and quantity of cervical mucus; ovulation is marked by an increase in mucus that becomes sticky and then clearer and slippery, Syn.ovulation method
The Collaborative International Dictionary of English (GCIDE) v.0.53Collaborative International Dictionary (GCIDE)
n. (Physiol.) The formation of ova or eggs in the ovary, and the discharge of the same. In the human female the discharge occurs about halfway between menstruation times. [ 1913 Webster +PJC ]