[take] lightly
1
to not treat a situation or problem with the seriousness or importance it deserves
- You shouldn't take the doctor's advice lightly.
- She didn't take lightly the responsibility of leading the project.
- It's important not to take lightly the potential risks of starting a new business.
- He realized too late that he had taken lightly the warning about the severe weather.
- The coach made it clear that he would not take lightly any breach of the team's code of conduct.