Synonym

A synonym is a word or phrase that means exactly or nearly the same as another word or phrase in the same language. Words that are synonyms are said to be synonymous, and the state of being a synonym is called synonymy. The word comes from Ancient Greek sýn (; "with") and ónoma (; "name"). An example of synonyms are the words begin, start, commence, and initiate. Words can be synonymous when meant in certain senses, even if they are not synonymous in all of their senses. For example, if one talks about a long time or an extended time, long and extended are synonymous within that context. Synonyms with exact meaning share a seme or denotational sememe, whereas those with inexactly similar meanings share a broader denotational or connotational sememe and thus overlap within a semantic field. Some academics call the former type cognitive synonyms to distinguish them from the latter type, which they call near-synonyms.

Some lexicographers claim that no synonyms have exactly the same meaning (in all contexts or social levels of language) because etymology, orthography, phonic qualities, ambiguous meanings, usage, etc. make them unique. Different words that are similar in meaning usually differ for a reason: feline is more formal than cat; long and extended are only synonyms in one usage and not in others (for example, a long arm is not the same as an extended arm). Synonyms are also a source of euphemisms.

In the figurative sense, two words are sometimes said to be synonymous if they have the same connotation:

...a widespread impression that ... Hollywood was synonymous with immorality...

Metonymy can sometimes be a form of synonymy, as when, for example, the White House is used as a synonym of the administration in referring to the U.S. executive branch under a specific president. Thus a metonym is a type of synonym, and the word metonym is a hyponym of the word synonym.

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