"My fault" is an expression commonly used to admit one's own wrongdoing or mistake. However, there are many synonyms that can be used to convey the same message. Some words that can be used interchangeably with "my fault" include: my error, my oversight, my blunder, my slip-up, my mistake, my mishap, my faux pas, my misstep, my lapse in judgment, and my failure. While these words may have slightly different connotations, they all acknowledge personal fault or responsibility for a negative outcome or situation. Using these synonyms can add variety and nuance to our language, while also helping us to take ownership of our actions.