a fortiori

[Latin, With stronger reason.] This phrase is used in logic to denote an argument to the effect that because one ascertained fact exists, therefore another which is included in it or analogous to it and is less improbable, unusual, or surprising must also exist.

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a fortiori (pronounced ah-for-she-ory) prep. Latin for "with even stronger reason," which applies to a situation in which if one thing is true then it can be inferred that a second thing is even more certainly true. Thus, if Abel is too young to serve as administrator, then his younger brother Cain certainly is too young.

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a fortiori adverb above all, accordingly, all the more, by a stronger reason, by inference, certainly, chiefly, consequently, ergo, especially, even more, for a certainty, for a still stronger reason, in chief, in the main, mainly, over and above, paramountly, particularly, primarily, thus, with the greater force

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See also: analytical, discursive