なさる

1. 1To do something, said respectfully of a superior, customer, or other person you are elevating.Ex. 1
2. 2In the form Noun + に + なさる, to decide on or choose something (respectful version of 〜にする).Ex. 2

It is formal and respectful, used when speaking to or about superiors, clients, and customers, especially in business and service settings. Staff often ask customers 〜になさいますか when taking orders. For the speaker's own actions, the humble form いたす is used instead.

• いらっしゃるN4「いらっしゃる」 is the honorific for 「いる」, 「行く」, and 「来る」, while 「なさる」 is the honorific for 「する」; they cannot be swapped. Use 「いらっしゃい」 to welcome guests, whereas 「なさい」 is a command form and must not be used toward superiors.
• なさいN4「なさい」 is formally the imperative form of 「なさる」, but it expresses commands from a superior to a subordinate or instructions on test questions, attaching to the ます-stem (e.g., 「起きなさい」), and cannot be used toward superiors; 「なさる」 is an honorific that elevates the other person's action, so the two are not interchangeable.
• 〜ていただくN4「なさる」 is honorific speech that takes the other person or a superior as the subject and directly elevates their action; 「〜ていただく」 is a humble expression that takes the benefiting party (oneself) as the subject with the doer marked by 「に」, emphasizing receiving a favor, and can also form polite requests. The two differ in perspective and cannot be directly substituted.
• ございますN4「ございます」 is the polite form of 「ある」 and 「です」, expressing existence, judgment, or attaching to adjectives via the onbin sound change, showing politeness to the listener without elevating the person being talked about; 「なさる」 is the honorific for 「する」 that elevates the doer. The two cannot be interchanged.
• でございますN4「でございます」 is a polite way of saying 「です」, attaching to nouns or the stem of な-adjectives to express judgment or explanation, and it only shows the speaker's politeness without elevating anyone else; 「なさる」 replaces 「する」 to elevate the person performing the action. They cannot be swapped.
• させてくださいN4「なさる」 elevates the actions of the other person or a third party and cannot be used for oneself; 「させてください」 asks the listener for permission for oneself or one's own group to do something, attaching to the causative form of a verb with a neutral register. The two cannot be interchanged.

なさる is the honorific of する, while いらっしゃる is the honorific of いる/行く/来る, and ございます/でございます are polite forms of ある/です rather than honorifics for someone's action. なさい is a command used toward inferiors, 〜ていただく humbly expresses receiving a favor, and させてください asks permission for the speaker's own action.