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called, named, known as

Generally do not use quotation marks around terms following these words except for clarity and to indicate coined words, direct quotations, or words not used in their literal or accepted sense:
            school of fish known as blacksmiths
            pot called a pipkin
but     called a "republic"

For nicknamed, see entries below.

See so-called and for proper nouns see also:
            Epithets and Appellations
            Nicknames of Persons
            Nicknames of Places and Things