Determined, accepted, assured, defined, and definite are all synonyms for certain. Unthinkable, doubtful, possible, unlikely, and unreliable are these antonyms of certain. And here are another 101 synonyms for certain.
Certain Synonyms
1. unquestionable
- Accepted
- Acknowledged
- As sure as eggs is eggs
- Assured of doing something
- Assured
- Automatic
- Beyond doubt
- Beyond question
- Bound to happen
- Bound
- Clear
- Conclusive
- Confirmed
- Definite
- Dependable
- Destined
- Effective
- Efficacious
- Evident
- Fated
- Foolproof
- Guaranteed
- In the bag
- Incontestable
- Incontrovertible
- Indisputable
- Indubitable
- Ineluctable
- Inescapable
- Inevitable
- Inexorable
- Infallible
- Irrefutable
- Manifest
- Nailed on
- Necessary
- Not in doubt
- Not in question
- Obvious
- Out of one's hands
- Palpable
- Patent
- Plain
- Predestined
- Predictable
- Recognized
- Reliable
- Sound
- Sure to happen
- Sure-fire
- Sure
- Tested
- There are no two ways about it
- Transparent
- Tried and tested
- Trusted
- Trustworthy
- Unavoidable
- Unchallenged
- Uncontested
- Undeniable
- Undisputed
- Undoubted
- Unequivocal
- Unerring
- Unfailing
- Unmistakable
- Unpreventable
- Unquestionable
- Unquestioned
- Very likely
- Sovereign
2. sure
- Assured
- Confident
- Convinced
- Easy in one's mind
- Have no doubt
- In no doubt
- Not question
- Persuaded
- Positive
- Satisfied
- Secure in one's belief
- Sure
- Unshaken in one's belief
- Hold the unwavering view
3. determined
- Defined
- Definite
- Determined
- Established
- Exact
- Explicit
- Express
- Fixed
- Individual
- Particular
- Precise
- Special
- Specific
- Especial