breaking point

WordReference Random House Unabridged Dictionary of American English © 2025

break′ing point′, 

1. the point at which a person, object, structure, etc., collapses under stress.
2. the point at which a situation or condition becomes critical.
• 1895–1900

Collins Concise English Dictionary © HarperCollins Publishers::

breaking point noun

1. the point at which something or someone gives way under strain