What does which mean?
Which is a central English question and linking word used to identify a person, thing, option, or course of action. On its own, it asks the listener or reader to select or name something: “Which one do you prefer?” When placed before a noun, it functions as a determiner, as in “Which route did you take?” In relative clauses, which refers back to a preceding noun or statement and supplies identifying or explanatory information, as in “The proposal which won support was revised.” It may also refer to an entire preceding clause, particularly in nonrestrictive clauses introduced by a comma. Which is distinct from whether, which concerns alternatives or the possibility that something is true. Although its grammatical roles vary, which remains straightforward: it signals that a choice, identity, or relationship must be specified.
Used independently to ask for the identity or selection of a particular person, thing, option, or result.
"Which of the two methods produced the more accurate result?"
It is especially common when the possible choices are already known or have been mentioned.
Used before a noun to ask the listener or reader to identify a particular person, thing, or option.
"Which version of the report should we circulate?"
This use directly determines the following noun and is common in both direct and indirect questions.
Introduces a relative clause that identifies a preceding person or thing or comments on a preceding statement.
"The manuscript which the curator discovered contained several unpublished letters."
When referring to an entire preceding statement, which is normally set off by commas: “The delay was unavoidable, which surprised the organizers.”
Which preserves an Old English question word that has been asking English speakers to make choices for more than a thousand years.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does which come from?
Which comes from Old English hwilc, also recorded as hwelc, meaning “of what kind” or “which one.” The Old English form developed into Middle English which and was established in its modern interrogative and relative uses by the late medieval period. Related words survive in other Germanic languages, including Dutch welk, German welcher, and Danish hvilken.
Related word forms
How which is actually used
Which is neutral in register and common in both formal and informal English. In restrictive relative clauses, that is often preferred, especially in American English, while nonrestrictive clauses normally use which. In indirect questions, the usual subject–verb order is retained, as in “I wonder which option she chose.”
Easily confused with which
Which selects or identifies an option, whereas whether presents alternatives or asks whether something is the case.
Who refers to people, while which can refer to people, things, options, or an entire preceding statement.
Witch is a noun denoting a person associated with magic, pronounced with the same final sound but with an initial /w/.