Equiprobability

Part of speech: noun

Definitions

1. The condition where all outcomes of a probability experiment have the same likelihood of occurrence
2. A situation in statistics where each possible event has an equal chance of happening within a defined framework
3. The state of having equal probabilities assigned to all possible results in a stochastic process

Etymology: "Equiprobability" is a plain compound, built from the Latin prefix "equi-" meaning "equal" and the English noun "probability." The prefix goes back to Latin "aequus," meaning "level" or "equal," whose ancestry reaches into Old Latin "aiquos" and a Proto-Italic form, so the idea of evenness has been in the word's roots for a very long time. The second half, "probability," comes from Latin "probabilitas," derived from "probabilis," meaning "worthy of approval" or "credible." Over time the sense shifted from something being worthy of belief to a measure of how likely an outcome is. Joining it to "equi-" yields a precise statistical term: a set of outcomes where none is favored over another, each carrying the same chance of occurring.