Antonyms for probability

attribute:

improbability.

likelihood of something happening:

reality, certainty, improbability, unlikelihood.

noun:

dubiousness, implausibility, incredibleness, impracticability, unlikeliness, unlikelihood, incredibility, doubtfulness, impracticality.

Paraphrases for Probability:

• Noun, singular or mass :
  ability, applicability, assumption, availability, belief, believe, believing, bet, blessing, candidate, capability, certainty, chance, confidence, consequence, contingency, danger, degree, doubt, event, eventuality, evidence, expectation, exposure, extent, facility, fact, faith, feasibility, field, fortune, gamble, guess, harm, hazard, hope, hypothesis, illusion, impact, implication, impression, indication, iuck, length, level, likelihood, limb, luck, margin, men, might, misconception, notion, occasion, occurrence, Opportunities, opportunity, optimism, option, outlook, perception, peril, plausibility, playing, possibility, potential, premise, presumption, probabilistic, prognosis, proportion, proposition, random, randomness, rate, ratio, reasonableness, risk, risk-taking, scenario, security, shot, success, suitability, supposition, susceptibility, suspicion, tendency, theory, thesis, thinking, threat, trust, venture, viability, vulnerability.
• Proper noun, singular :
  ability, availability, chance, feasibility, hazard, likelihood, likely, opportunity, Possibilities, possibility, possible, potential, probable, report.