Legal maxim

A Legal Maxim is an established principle or proposition. The Latin term, apparently a variant on maxima, is not to be found in Roman law with any meaning exactly analogous to that of a legal maxim in the Medieval or modern sense of the word, but the treatises of many of the Roman jurists on Regular definitions, and Sententiae juris are, in some measure, collections of maxims. Most of the Latin maxims developed in the Medieval era in European countries that used Latin as their language for law and courts.
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A mensa et thoro - From bed and board.

A vinculo matrimonii - From the bond of matrimony.

Ab extra - From outside.

Ab initio - From the beginning.

Absoluta sententia expositore non indiget - An absolute judgment needs no expositor.

Abundans cautela non nocet - Abundant caution does no harm.
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