law of definite proportions

noun phrase

: a statement in chemistry: every definite compound always contains the same elements in the same proportions by weight

Word History

First Known Use

1830, in the meaning defined above

Time Traveler
The first known use of law of definite proportions was in 1830

Dictionary Entries Near law of definite proportions

law of cosines

law of definite proportions

law of demand

See More Nearby Entries 

Cite this Entry

“Law of definite proportions.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/law%20of%20definite%20proportions. Accessed 28 Nov. 2024.

Copy Citation

Share

Kids Definition

law of definite proportions

: a law of chemistry that states that every definite compound always contains the same elements in the same proportions by mass

Medical Definition

law of definite proportions

noun
law of def·​i·​nite pro·​por·​tions -ˈdef-(ə-)nət-prə-ˈpȯr-shənz How to pronounce law of definite proportions (audio)
: a statement in chemistry: every definite compound always contains the same elements in the same proportions by weight

More from Merriam-Webster on law of definite proportions

Britannica.com: Encyclopedia article about law of definite proportions

Love words? Need even more definitions?

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

Popular in Grammar & Usage

See All

How to Use Em Dashes (—), En Dashes (–) , and Hyphens (-)

Plural and Possessive Names: A Guide

The Difference Between 'i.e.' and 'e.g.'

Why is '-ed' sometimes pronounced at the end of a word?

What's the difference between 'fascism' and 'socialism'?
See All

Popular in Wordplay

See All

Terroir, Oenophile, & Magnum: Ten Words About Wine

8 Words for Lesser-Known Musical Instruments

10 Words from Taylor Swift Songs (Merriam's Version)

9 Superb Owl Words

15 Words That Used to Mean Something Different
See All

Games & Quizzes

See All
Play Quordle: Guess all four words in a limited number of tries. Each of your guesses must be a real 5-letter word.
Quordle Can you solve 4 words at once?
Play Blossom: Solve today's spelling word game by finding as many words as you can using just 7 letters. Longer words score more points.
Blossom Word Game Pick the best words!
Play Missing Letter: a crossword with a twist. Each of the 25 puzzle words start with a different letter of the alphabet. Which letter is missing?
Missing Letter A daily crossword with a twist
little chihuahua dressing like a turkey for thanksgiving
Is That Gratitude or Attitude? A Thanksgiving Quiz Decide which words express gratitude and which gi...