Number Prefixes: tri (three)

Learn these words beginning with the prefix tri-, meaning "three."
11 words 104 learners

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Full list of words from this list:

words only definitions & notes
  1. triangle
    a three-sided polygon
  2. tripod
    a three-legged rack used for support
  3. trilogy
    a set of three literary or dramatic works related in subject
  4. triathlon
    an athletic contest consisting of three different events
  5. trimester
    a period of three months
  6. trident
    a spear with three prongs
  7. trigonometry
    the mathematics of three-sided figures and their functions
  8. trilobite
    an extinct arthropod with a three-part exoskeleton
  9. triplet
    one of three siblings born at the same time
  10. triceps
    any skeletal muscle having three origins
  11. triad
    a set of three similar things considered as a unit
Created on Tue Jun 03 20:34:18 EDT 2025 (updated Fri Jun 06 13:58:08 EDT 2025)

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