side effect(redirected from a side-effect)
1. An unpleasant symptom experienced while taking a particular medication. Often plural. Unfortunately, nausea is a common side effect with this drug. Ugh, I had so many side effects that I had to stop taking that medication.
2. By extension, an unexpected result or consequence of something. Having to drive my little sister all over the place is an annoying side effect of living at home again.