A fact of life Definition 1 of 4Pro Tip 1/3Unavoidable Truth Refers to truths that are often negative but must be accepted as part of life. Growing old is an uncomfortable fact of life. Pro Tip 2/3Acceptance Required Implies that resistance is futile and embracing the situation is necessary. Paying bills is just a fact of life. Pro Tip 3/3Often Negative Usually refers to something not desired or considered a drawback in life. Frequent layoffs have become a fact of life in this industry.