1. Philosophy The doctrine that probability is a sufficient basis for belief and action, since certainty in knowledge is unattainable.
2. Roman Catholic Church The system of moral theology that applies when the lawfulness of an act is uncertain, by allowing an actor to follow an opinion favoring personal liberty if that opinion is solidly probable, even though an opposing opinion, favoring law, is more probable.
proba·bi·list adj. & n.
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Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.