Open English Wordnet
Nouns
(n)possibility, possiblenesscapability of existing or happening or being true“there is a possibility that his sense of smell has been impaired”
(n)hypothesis, possibility, theorya tentative insight into the natural world; a concept that is not yet verified but that if true would explain certain facts or phenomena“a scientific hypothesis that survives experimental testing becomes a scientific theory”, “he proposed a fresh theory of alkalis that later was accepted in chemical practices”