Many people would bet a month's salary on an event with such a probability.
Scientists analyzing their experimental data are also cautious.
Accordingly, scientists have developed a careful language to describe a promising result. If the significance is greater than 5 sigma it is a discovery. In between, there are various shades of gray. It is the decisive parameter of the Gaussian curve, a mathematical function that describes the distribution of data from many simple experiments. Citing a certain number of sigma directly translates into a probability.