1. opined, supposed ...c1450 obs.
2. obstinate in opinion; opinionated ...1491 obs.
to give an opinion; to pronounce a formal or authoritative opinion
...1625 obs. rare
from Latin opinatus pa. pple. of opinari to opine, to be of opinion
FIRST DOCUMENTED USE
c1450 (adj. 1) "...myn opinate riȝtwesnes for defending..."
From: De Imitatione Christi
The Earliest English translation, c1450
EXAMPLE (adj. 2)
..."He had condescended to make it to that other whiche was opynate."
From: Vitas Patrum
Translated By: William Caxton, 1491
• A New English Dictionary on Historical Principles,
James Murray, 1887-1933