Ten to one Definition 1 of 3Pro Tip 1/3Expectation Strength Highlights a strong expectation; something is very likely to occur. Ten to one, they'll announce their engagement soon. Pro Tip 2/3Informal Prediction Used in casual, informal conversations to predict outcomes. Ten to one, it'll rain during our picnic tomorrow. Pro Tip 3/3Not Literal Odds It's not meant to provide actual betting odds—it's just an expression. Ten to one, the favorite team will win the match.