Trophoblast
/ˈtroʊ.fəˌblæst/noun
The outer cell layer of the early embryo that helps form the placenta.
Did you know?The second half comes from Greek blastos, “sprout” or “bud,” a root also seen in scientific words for early growth and budding cells, making embryology sound weirdly botanical.
Etymological Timeline
Ancient Greek
Greek
trophḗ
“nourishment, food”
Ancient Greek
Greek
blástos
“sprout, bud, germ”
19th Century
French/Medical Greek
trophoblaste
“the outer cell layer of the developing embryo”
Late 19th Century
English
trophoblast
“the outer layer of cells forming part of the placenta in mammals”
Modern English
English
trophoblast
“the outer cell layer of the early embryo that contributes to placenta formation”
Explore more surprising origins