also: とゆう
expression
Used to quote or refer to something by name, or to indicate what someone says. Often follows a noun, phrase, or clause.
これは「桜」という花です。
This is a flower called 'sakura'.
彼は明日来るという。
He says he will come tomorrow.
expression
as many as; as much as
Follows a quantity or number to emphasize the amount, often with a sense of surprise or significance.
彼は一億円という大金を寄付した。
He donated a huge sum of as much as 100 million yen.
expression
all ...; every single ...
Used in the pattern AというA to emphasize that every instance of A is included, without exception.
店という店が閉まっていた。
Every single shop was closed.
Combination of the case particle と (quotative) and the verb 言う (to say). The kana spelling という is standard for this grammaticalized expression.