the.com/gentleman

means A man who conducts himself with courtesy, consideration, and honor — originally a social rank, now mostly a measure of character.

from Built from 'gentle' (in its old sense of 'well-born' or 'noble,' from Latin gentilis, 'of the same clan or family') plus 'man.' In medieval England a gentleman was simply a step below nobility — a man of good birth entitled to a coat of arms, not necessarily a kind one. Over centuries the word drifted from bloodline to behavior: by the 1700s and 1800s, 'gentleman' increasingly meant someone who acted the part — courteous, honest, self-controlled — whether or not his ancestry backed it up. The rank faded; the manners stuck.