To prognosticate is to predict or forecast something.
An agnostic is a person who believes that it is impossible to know conclusively whether or not God exists; an agnostic can be doubtful about other things as well.
identifying the nature or cause of some phenomenon
concerned with diagnosis
of or relating to Gnosticism
a prediction about how something (as the weather) will develop
of or relating to prediction
a sign of something about to happen
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