uncertain
An antonym (opposite) for certain is maybe not certain
certain
The opposite of doubt is certainty. The opposite of a doubt about a person could be trust.
An antonym would be, "I was uncertain/unsure to ask help on the assignment." Both words are the opposite of certain.
Uncertain
Uncertain.
uncertain
There's no certain opposite, but an alternative would be: Popeye's spinach
Certain, absolute,
certain Confident
The opposite of uncertain is certain. When something is certain, it is definite, known, or sure, leaving no room for doubt or ambiguity. Certainty implies confidence in the outcome or truth of a situation.
because it isn't the opposite