Picture of Wisdom Teeth

Wisdom tooth: One of the large molars in the very back of the jaw. The human jaw has changed in size over the course of evolution, and wisdom teeth are no longer needed, but they continue to erupt in many individuals. If the jaw is too small to accommodate them, they may cause pain or crowd other teeth out of position. The wisdom teeth may need to be surgically removed.
Text: MedicineNet - Dental Health and Wisdom Teeth
and MedTerms™ Medical Dictionary by MedicineNet, Inc.