| invincible(adjective, strong, certain, resolute) |
| incontestable(adjective, hard, certain, true) |
| inarguable(adjective, certain, true, definite) |
| unimpeachable(adjective, pure, certain, unquestionable) |
| indubitable(adjective, certain, true, unquestionable) |
| ironclad(certain, unquestionable, indisputable) |
| sure(adjective, certain, true, safe) |
| unanswerable(certain, definite, unquestionable, indisputable) |
| certain(adjective, hard, certain, true) |
| evident(adjective, certain, definite, unquestionable) |
| irresistible(certain, unquestionable, indisputable, ironclad) |
| positive(adjective, certain, true, unquestionable) |
| accurate(certain, unquestionable, indisputable, undeniable) |
| apodictic(certain, unquestionable, indisputable, ironclad) |
| beyond question(expression, certain, definite, indisputable) |
| can bet on it(expression, idiom, certain, unquestionable) |
| double-checked(certain, evident, unquestionable, indisputable) |
| irrebuttable(certain, unquestionable, indisputable, ironclad) |
| nof ifs ands or buts(expression, idiom, certain, unquestionable) |
| obvious(certain, definite, unquestionable, indisputable) |