admissible

Capable or deserving to be admitted, accepted or allowed; allowable, permissible, acceptable.

Moreover, the term [...] is well recorded in British and Australian sources from the 1840s onwards, while the earliest Anglo-Indian evidence only extends as far back as 1865 and so does not hold precedence. Thus, deriving the term from Hindustani is not chronologically admissible on present evidence.

Describing a heuristic that never overestimates the cost of reaching a goal.