ETYMOLOGY
from Latin potat-, past participial stem of potare (to drink) + ‑ive
EXAMPLE
“… desireth to cure these or such like infectious diseases, must chiefly prepare and season the body with waters of cold and naturall hearbes, in the first and second degree, before the disease be possessed: then foorthwith flux the body, by some gentle and potatiue electuarie, in equall and artificial degree, fauourably casting out the infected humours. …”
From: The Flower of Phisicke
VVherein is perfectlie comprehended a true introduction and method for mans assured health
By William Clever, 1590
Lexicophilia 