What is a synonym for uncertain?

Here are some synonyms for "uncertain," depending on the specific nuance you want to convey:

General uncertainty:

* Ambiguous

* Doubtful

* Dubious

* Questionable

* Unclear

* Unsure

* Vague

Uncertainty about the future:

* Precarious

* Unpredictable

* Insecure

* Volatile

Uncertainty about something's truth or existence:

* Doubtful

* Skeptical

* Unconfirmed

* Unproven

Uncertainty about a decision or course of action:

* Hesitant

* Indecisive

* Wavering

* Ambivalent

The best synonym will depend on the context of your writing.