Eat one's words

Eat one's words

Meaning:

Admit that what you said was wrong.

If you eat your words, you admit that the statements or predictions you made were wrong.

Example:

Tom said Nancy would never succeed in her business, but after seeing her business grow, he had to eat his words.

I taught a grammar rule in my ESL class, and one of my students said I was wrong. After I checked it in dictionaries and asked other teachers, I found she was right. I had to eat my words in the next class.