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The suffix -san (さん), which is equivalent to all of "Mrs., Mr., Ms., Master, Miss, Mistress." is customary in addressing a person by name. This suffix is used with both surnames and given names, and failure to use it is called 呼び捨て (yobisute, literally "throwing away the name") and may be considered exceedingly rude, depending on the status of the person referred to. The formal equivalent of -san is -様 (-sama), and the fond diminutive equivalent is -chan (-ちゃん). Young boys and younger men are often addressed as -kun (-くん、君).