politely, courteously (adverb)

in a polite manner

"the policeman answered politely, `Now look here, lady...'"

courteously (Adverb)

In a courteous manner; with obliging civility or condescension; politely.

courteously

Etiquette () is the set of norms of personal behaviour in polite society, usually occurring in the form of an ethical code of the expected and accepted social behaviours that accord with the conventions and norms observed and practised by a society, a social class, or a social group. In modern English usage, the French word étiquette (label and tag) dates from the year 1750.