(with "the") Something certain.
Sure, positive, not doubting.
Determined; resolved.
Not to be doubted or denied; established as a fact.
Actually existing; sure to happen; inevitable.
Unfailing; infallible.
I have often wished , that I knew so certain a remedy in any other disease
Fixed or stated; regular; determinate.
Known but not specifically named; indeterminate; indefinite; one or some; sometimes used independently as a noun, and meaning certain persons; see also "one".
(with of) Unnamed or undescribed members (of).