1. The seventh Sunday after Easter, commemorating the descent of the Holy Spirit upon the disciples. Also called Whitsunday.
2. Judaism. See Shavuot.

[Middle English pentecoste, from Old English Pentecosten, from Late Latin Pentēcostē, from Greek pentēkostē (hēmerā), fiftieth (day), feminine of pentēkostos, fiftieth, from pentēkonta, fifty.]

The American Heritage® Dictionary of the English Language, Fourth Edition Copyright © 2007, 2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved.