1. Lacking or indicating lack of confidence or assurance
   "uncertain of his convictions"; "moving with uncertain steps"; "an uncertain smile"; "touched the ornaments with uncertain fingers";
   - unsure, incertain [non-standard]
    
2. Not established beyond doubt; still undecided or unknown
   "a manuscript of uncertain origin"; "plans are still uncertain"; "changes of great if uncertain consequences"; "without further evidence his story must remain uncertain"; "an uncertain future";
   - unsure
    
3. Not certain to occur; not inevitable
   "everything is uncertain about the army"; "the issue is uncertain"
    
4. Ambiguous (especially in the negative)
   "she spoke in no uncertain terms"
    
5. Not consistent or dependable
   "an uncertain recollection of events"; "a gun with a rather uncertain trigger"
    
6. Not established or confirmed
   "his doom is as yet uncertain";
   - unsealed
    
7. Subject to change
   "the weather is uncertain";
   - changeable, unsettled
    
8. Physically unstable or shaky in movement
   "uncertain steps in the dark";
   - unsteady

See also: ambiguous, ambivalent, assurance, authority, cert [Brit, informal], certainty, chancy, confidence, contingent, dead cert [Brit, informal], doubtful, dubious, flakey [informal], flaky [informal], flukey [informal], fluky [informal], foregone conclusion, groping, iffy, indefinite, indeterminate, self-assurance, self-confidence, sure thing, sureness, undependable, undetermined, unpredictable, unreliable, up in the air, variable

Antonym: certain

Encyclopedia: Uncertain, Texas