To fail to notice or consider something, usually by mistake.
I overlooked a typo in the report.
We overlooked an important detail.
This usually happens by accident. If you notice the problem but choose not to punish or criticize it, the word has a different meaning.
Common phrases & grammar
overlook an important detail · overlook a typo · overlook a problem
overlook + a detail/problem/mistake
overlook + the fact that + sentence