1. Likely to happen or to be true: War seemed probable in 1938. The home team, far ahead, is the probable winner.
2. Likely but uncertain; plausible.
3. Theology Of or relating to opinions and actions in ethics and morals for whose lawfulness intrinsic reasons or extrinsic authority may be adduced.
[Middle English, plausible, from Old French, from Latin probābilis, from probāre, to prove; see PROVE.]
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