Hubble constant

Hub·​ble constant | \ ¦həbəl- \

Definition of Hubble constant

: a proportionality constant indicative of the rate of expansion of the universe that is used in relating the apparent velocity of recession of a distant galaxy and its distance

Love words?

You must — there are over 200,000 words in our free online dictionary, but you are looking for one that’s only in the Merriam-Webster Unabridged Dictionary.

Start your free trial today and get unlimited access to America's largest dictionary, with:

  • More than 250,000 words that aren't in our free dictionary
  • Expanded definitions, etymologies, and usage notes
  • Advanced search features
  • Ad free!

History and Etymology for Hubble constant

after Edwin P. Hubble †1953 American astronomer

Keep scrolling for more

Learn More about Hubble constant

Statistics for Hubble constant

Cite this Entry

“Hubble constant.” Dictionary, Merriam-Webster, Accessed 22 Jan. 2021.

Comments on Hubble constant

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


Test Your Vocabulary

Slippery Words Quiz—Changing with the Times

  • ducreux self portrait yawning
  • What is an earlier meaning of nice?
Name That Thing

Test your visual vocabulary with our 10-question challenge!

Universal Daily Crossword

A daily challenge for crossword fanatics.

Love words? Need even more definitions?

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