Probability is the measure of the likelihood that an event will occur. See glossary of probability and statistics. Probability is quantified as a number between 0 and 1, where, loosely speaking, 0 indicates impossibility and 1 indicates certainty. The higher the probability of an event, the more likely it is that the event will occur. A simple example is the tossing of a fair (unbiased) coin. Since the coin is fair, the two outcomes ("heads" and "tails") are both equally probable; the probability of "heads" equals the probability of "tails"; and since no other outcomes are possible, the probability of either "heads" or "tails" is 1 / 2 (which could also be written as 0.5 or 50 %).

Based on this passage, which term is defined as the chance that a given event will occur? Let's think fast. Stream of consciousness:
To answer the question, consider the following: Probability is the measure of the likelihood that an event will occur. So the final answer is Probability.