[ wuhn ]
/ wʌn /




Idioms for one

Origin of one

before 900; Middle English oon, Old English ān; cognate with Dutch een, German ein, Gothic ains, Latin ūnus (OL oinos); akin to Greek oínē ace on a die

usage note for one

One as an indefinite pronoun meaning “any person indefinitely, anyone” is more formal than you, which is also used as an indefinite pronoun with the same sense: One (or you ) should avoid misconceptions. One (or you ) can correct this fault in three ways. When the construction requires that the pronoun be repeated, either one or he or he or she is used; he or he or she is the more common in the United States: Wherever one looks, he (or he or she ) finds evidence of pollution. In speech or informal writing, a form of they sometimes occurs: Can one read this without having their emotions stirred?
In constructions of the type one of those who (or that or which ), the antecedent of who is considered to be the plural noun or pronoun, correctly followed by a plural verb: He is one of those people who work for the government. Yet the feeling that one is the antecedent is so strong that a singular verb is commonly found in all types of writing: one of those people who works for the government. When one is preceded by only in such a construction, the singular verb is always used: the only one of her sons who visits her in the hospital.
The substitution of one for I, a typically British use, is usually regarded as an affectation in the United States. See also he1, they.


one wan won (see usage note at the current entry)

Definition for one (2 of 2)


a suffix used in the names of ketones and analogous chemical compounds: lactone; quinone.

Origin of -one

perhaps < Greek -ōnē feminine patronymic

Example sentences from the Web for one

British Dictionary definitions for one (1 of 2)

/ (wʌn) /




Other words from one

Related prefixes: mono-, uni- Related adjective: single

Word Origin for one

Old English ān, related to Old French ān, ēn, Old High German ein, Old Norse einn, Latin unus, Greek oinē ace

British Dictionary definitions for one (2 of 2)


suffix forming nouns

indicating that a chemical compound is a ketone acetone

Word Origin for -one

arbitrarily from Greek -ōnē, feminine patronymic suffix, but perhaps influenced by -one in ozone

Medical definitions for one



A ketone:acetone.
A compound that contains oxygen, especially in a carbonyl radical:lactone.

Scientific definitions for one


A suffix used to form the names of chemical compounds containing an oxygen atom attached to a carbon atom, such as acetone.

Idioms and Phrases with one