Merriam-Webster Logo
SINCE 1828
Menu
dictionary thesaurus

octad

noun
oc·​tad | \ ˈäkˌtad\
plural -s

Definition of octad

: a group or arrangement of eight especially : a group of eight figures representing consecutive powers of ten in ancient mathematical notation

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 octad

Greek oktad-, oktas number eight, body of eight men, from okta- octa- + -ad-, -as -ad

Keep scrolling for more

Learn More about octad

Statistics for octad

Look-up Popularity

Comments on octad

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

Show Comments  Hide Comments 

WORD OF THE DAY

assiduous

Listen to the pronounciation of assiduous

showing great care, attention, and effort

Get Word of the Day daily email!

Test Your Vocabulary

Finance Words Quiz

  • a-piggy-bank
  • The etymology of mortgage is related most closely to which two words?
How Strong Is Your Vocabulary?

Test your vocabulary with our 10-question quiz!

TAKE THE QUIZ
Syn City

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!

Words at Play
Ask the Editors
Word Games