Synonyms: polite, mannerly, civil, courteous, genteel
These adjectives mean mindful of, conforming to, or marked by good manners. Polite and mannerly imply consideration for others and the adherence to conventional social standards of good behavior: "She was so polite and unwilling to offend that she wouldn't always make her feelings and intentions clear" (Jane Mayer and Jill Abramson)."Just the one young man came out, very mannerly, and helped first her then me down from the car" (Alice Munro).
Civil often suggests the barest observance of accepted social usages, as in the avoidance of rudeness: "Mr. Bingley was unaffectedly civil in his answer, and forced his younger sister to be civil also, and say what the occasion required" (Jane Austen).
Courteous implies courtliness and dignity: "Even around his parents ... he's unfailingly courteous and even-tempered, letting slide their mild attempts to run his life" (Paul Solotaroff).
Genteel, which originally meant well-bred, now usually suggests excessive and affected refinement associated with the upper classes: "In a world without credit bureaus, background checks, or official identification, properly genteel attire, speech, and behavior determined where a person could go, whom he could see, and how he was judged in every area" (Jeffrey L. Pasley).