Meaning of “oestrogen” - Learner’s Dictionary

oestrogen

noun [ U ] UK (US estrogen) uk us /ˈiːstrəʊdʒən/ US  /ˈestrədʒən/

a chemical substance in a woman's body that prepares her eggs for fertilization (= joining with the male seed to make a baby)

(Definition of “oestrogen” from the Cambridge Learner’s Dictionary © Cambridge University Press)