Definition of quantum number
: any of a set of numbers that indicate the magnitude of various discrete quantities (such as electric charge) of a particle or system and that serve to define its state
Keep scrolling for more
Comments on quantum number
What made you want to look up quantum number? Please tell us where you read or heard it (including the quote, if possible).
Test Your Vocabulary
Slippery Words Quiz—Changing with the Times
- What is an earlier meaning of nice?
Test your visual vocabulary with our 10-question challenge!
TAKE THE QUIZ
Spell words. Make bears.
TAKE THE QUIZLove words? Need even more definitions?
Merriam-Webster unabridgedWords at Play
Ask the Editors
Word Games
Share quantum number
Time Traveler for quantum number
The first known use of quantum number was in 1902
See more words from the same year