Origin of which
usage note for which
Words nearby which
WHICH VS. THAT
What’s the difference between which and that?
Which and that are used in very similar ways (especially to introduce clauses that refer back to an earlier part), but there is often a key difference.
Before we get into the grammar, let’s take a look at two similar sentences, one using that and one using which.
I wrote about my favorite movie that was released in 1994.
I wrote about my favorite movie, which was released in 1994.
Both sentences are about a movie. But there’s a difference in what’s being communicated.
In the first sentence (the one using that), the speaker is indicating that the movie they wrote about is their favorite movie released in 1994—not necessarily their favorite movie in general.
In the second sentence (the one using which), the speaker is saying that the movie is their favorite in general, while also mentioning that it was released in 1994. In this sentence, you could take away the part that starts with which and the sentence would retain the same basic meaning.
But that’s not true of the first sentence—taking away that was released in 1994 would alter the meaning of the sentence.
That’s because that was released in 1994 is what’s called a restrictive clause, which is a part of a sentence that provides essential information about the part before it. A restrictive clause can’t be removed without changing the essential meaning of the sentence.
The second sentence (the one using which), ends in a nonrestrictive clause, which provides nonessential information—information that can be removed without altering the main message of the sentence. Usually, nonrestrictive clauses are marked off by commas (or em dashes). Think of a nonrestrictive clause as an aside—additional information mentioned along the way.
This grammatical distinction between that and which is largely used in formal American English. In informal speech, it is very common to use that and which interchangeably. And sometimes the difference in what they convey is very subtle or practically nonexistent.
Still, when used in clauses like the ones in our examples, which is usually preceded by a comma, but that is not.
Want to learn more? Read the full breakdown of the difference between which and that.
Quiz yourself on which vs. that!
Should which or that be used in the following sentence?
The cat ____ I saw yesterday has come back.
How to use which in a sentence
So I've worked out a plan by-which you can examine the invention and test its profits without risking one penny.
His declaration means that he believes in "That-which-is-above-Things."Dynamic Thought|William Walker Atkinson
By the way, I wonder if I ought to tell him about the silver which-not.Berry And Co.|Dornford Yates
We just cant afford to have our goods floating around every-which-way right in the start.Motor Boat Boys' River Chase|Louis Arundel
We went into another field—behind us and before us, and every which-a-way we looked, we seen a rhinusorus.Bransford of Rainbow Range|Eugene Manlove Rhodes
British Dictionary definitions for which
- used with a noun in requesting that its referent be further specified, identified, or distinguished from the other members of a classwhich house did you want to buy?
- (as pronoun)which did you find?
- (used in indirect questions)I wondered which apples were cheaper
- whatever of a class; whicheverbring which car you want
- (as pronoun)choose which of the cars suit you
Word Origin for which
Other Idioms and Phrases with which
In addition to the idioms beginning with which
- which is which
- which way the wind blows
- every which way
- know which side of bread is buttered
- (which) way the wind blows