(ä fôr'tē-ôr'ē, ā fōr'tē-ō'rī') adv. For a still stronger reason; all the more.
[Latin : ā, ab, from + fortiōrī, ablative of fortior, stronger.]
(Latin, from the stronger) Phrase used for ‘all the more’ or ‘even more so’: if all donkeys bray, then a fortiori all young donkeys bray.
((ラテン語))いっそう有力な理由で(for a stronger reason)；なおさら.
a fortiori analysis
In decision theory, an analysis made to intentionally favor alternative solutions
when compared to the solution adjudged as best. The alternatives are
deliberately weighted to make them look better. If the adjudged-best
solution still remains the best, its position as the likely choice is further strengthened. 'A fortiori' is Latin for, 'even more so' or 'more conclusively.