- the usual US spelling of oestrogen
WordReference Random House Learner's Dictionary of American English © 2026
es•tro•gen /ˈɛstrədʒən/USA pronunciation
n. [uncountable]
WordReference Random House Unabridged Dictionary of American English © 2026- Biochemistrya major female sex hormone that is produced in the ovaries and controls the reproductive cycle.
es•tro•gen
(es′trə jən),USA pronunciation n. [Biochem.]
- Biochemistryany of several major female sex hormones produced primarily by the ovarian follicles of female mammals, capable of inducing estrus, developing and maintaining secondary female sex characteristics, and preparing the uterus for the reception of a fertilized egg: used, esp. in synthetic form, as a component of oral contraceptives, in certain cancer treatments, and in other therapies.
- estr(us) + -o- + -gen 1925–30
Collins Concise English Dictionary © HarperCollins Publishers::
estrogen /ˈɛstrədʒən; ˈiːstrə-/ n
Collins Concise English Dictionary © HarperCollins Publishers::
oestrogen /ˈiːstrədʒən; ˈɛstrə-/, US estrogen n
- any of several steroid hormones, that are secreted chiefly by the ovaries and placenta, that induce oestrus, stimulate changes in the female reproductive organs during the oestrous cycle, and promote development of female secondary sexual characteristics
'estrogen' also found in these entries (note: many are not synonyms or translations):
oestrogen
- birth-control pill
- chorionic gonadotropin
- diethylstilbestrol
- ERT
- estradiol
- estriol
- estrogenic
- estrogen replacement therapy
- estrone
- hormone replacement therapy
- mestranol
- metestrus
- morning-after pill
- norethindrone
- norethynodrel
- norgestrel
- Ortho-Novum
- Pap test
- quinestrol
- tamoxifen