[ pahr-sek ]
/ ˈpɑrˌsɛk /
DON’T VACILLATE! VANQUISH THIS WORD OF THE DAY QUIZ!
It’d be a real faux pas to miss this quiz on the words from August 3–9, 2020!
Question 1 of 7
What does “vacillate” mean?
Words nearby parsec
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2020
British Dictionary definitions for parsec
/ (ˈpɑːˌsɛk) /
a unit of astronomical distance equal to the distance from earth at which stellar parallax would be 1 second of arc; equivalent to 3.0857 × 10 16 m or 3.262 light years
Word Origin for parsec
C20: from parallax + second ²
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Scientific definitions for parsec
[ pär′sĕk′ ]
A unit of astronomical length equal to 3.26 light-years. It is based on the distance from Earth at which a star would have a parallax of one second of arc. Its metric equivalent is about 30.8 trillion km (19.1 trillion mi). It is used in measuring distances in interstellar and intergalactic space. The closest star to Earth, Alpha Centauri, is about 1.3 parsecs away. Compare astronomical unit light-year.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.