sidereal time

noun

Definition of sidereal time 

1 : time based on the sidereal day

2 : the hour angle of the vernal equinox at a place

First Known Use of sidereal time

1765, in the meaning defined at sense 1

Keep scrolling for more

Learn More about sidereal time

Share sidereal time

Statistics for sidereal time

Look-up Popularity

Time Traveler for sidereal time

The first known use of sidereal time was in 1765

See more words from the same year

More from Merriam-Webster on sidereal time

Britannica.com: Encyclopedia article about sidereal time

Comments on sidereal time

What made you want to look up sidereal time? Please tell us where you read or heard it (including the quote, if possible).

WORD OF THE DAY

lying above or upon

Get Word of the Day daily email!

Test Your Vocabulary

Words from Greek and Roman Mythology Quiz

  • the-triumph-of-venus-by-alessandro-magnasco
  • Boreal comes from the name of the ancient Greek god of which wind?
Spell It

Can you spell these 10 commonly misspelled words?

TAKE THE QUIZ
SCRABBLE® Sprint

Test Your Knowledge - and learn some interesting things along the way.

TAKE THE QUIZ

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!