Gain access to thousands of additional definitions and advanced search features—ad free! JOIN NOW
: an equation expressing a measured value of some function of one or more unknown quantities
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:
Share observation equation
Resources for observation equation
Comments on observation equation
What made you want to look up observation equation? Please tell us where you read or heard it (including the quote, if possible).
to express warning or disapproval
Get Word of the Day daily email!
Autumn Words of the Day 2018
Can you spell these 10 commonly misspelled words?
Test Your Knowledge - and learn some interesting things along the way.
Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!
A cavalcade of words for travel
Two words. One hundred years.
Words from the week of 11/9/2018
There's always room for another article.
And is one way more correct than the others?
The story of an imaginary word that managed to sneak past our editors and enter the dictionary.
How to use a word that (literally) drives some people nuts.
The awkward case of 'his or her'
(Secret October WOTD Quiz)
Name that government! Or something like that.
A game of winding words.