/nawr'euh thuy"neuh dreuhl, naw reth"euh neuh drel'/ , n. Pharm.
a progestin, C 20 H 26 O 2 , used in combination with an estrogen in some oral contraceptives.
[ 1955-60; NOR- + ethyn ( yl ), components of 2 versions of its chemical name + -odrel, of uncert. derivation ]