prin·​cip·​i·​al | \ (ˈ)prin¦sipēəl \

Definition of principial

2 : of, relating to, or based on principle

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!

First Known Use of principial

14th century, in the meaning defined at sense 1

History and Etymology for principial

Latin principium beginning + English -al

Keep scrolling for more

Learn More about principial

Time Traveler for principial

Time Traveler

The first known use of principial was in the 14th century

See more words from the same century

Statistics for principial

Cite this Entry

“Principial.” Dictionary, Merriam-Webster, Accessed 10 Aug. 2020.

Comments on principial

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


Test Your Vocabulary

Original Meanings Quiz

  • rembrandt painting a young scholar and his tutor
  • Which of the following is the earliest known sense of the word awe?
Spell It

Can you spell these 10 commonly misspelled words?

Add Diction

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

Love words? Need even more definitions?

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