[cer.tain] adj [ME, fr. OF, fr. (assumed) VL certanus, fr. L certus, fr. pp. of cernere to sift, discern, decide; akin to Gk krinein to separate, decide, judge, OIr criathar sieve] (13c) 1: fixed, settled "a ~ percentage of the profit"
2: of a specific but unspecified character, quantity, or degree "the house has a ~ charm" 3 a: dependable, reliable "a ~ remedy for the disease" b: known or proved to be true: indisputable "it is ~ that we exist"
4. a: inevitable "the ~ advance of age" b: incapable of failing: destined--used with a following infinitive "she is ~ to do well"
5: assured in mind or action syn see sure -- for certain : as a certainty: assuredly
[2]certain pron, pl in constr (15c): certain ones