- Falling out is defined as a disagreement or something that causes two people to no longer be friendly with one another.
An example of a falling out is when two sisters fight over their inheritance and stop speaking to each other.
These two women have had a falling out.
falling-out definition by Webster's New World
falling-out definition by American Heritage Dictionary
noun pl. fall·ings-out or fall·ing-outs
A disagreement; a quarrel: a falling-out among family members.