Wisdom tooth Meaning, Definition & Usage

  1. noun any of the last 4 teeth on each side of the upper and lower jaw; the last of the permanent teeth to erupt (between ages 16 and 21)

WordNet


Definitions
  1. the last, or back, tooth of the full set on each half of each jaw in man; familiarly so called, because appearing comparatively late, after the person may be supposed to have arrived at the age of wisdom. See the Note under Tooth, 1.

Webster 1913