【Civil】 , 【polite】 , 【courteous】 , 【courtly】 , 【gallant】 , 【chivalrous】 are comparable as applied to persons or their words and acts when in intercourse with others with the meaning observant of the forms required by good breeding.

【Civil】 commonly suggests the bare fulfillment of the ordinary requirements of social intercourse; it frequently implies little more than forbearance from rudeness.

【Polite】 , while sometimes suggesting a merely perfunctory attitude, is more positive than 【civil】 ; it commonly implies thoughtfulness for the feelings of others, united with polish of manners and address.

【Courteous】 implies more considerate and dignified, 【courtly】 , more stately and ceremonious, observance of due civilities.

【Gallant】 and 【chivalrous】 imply 【courteous】  attentiveness to women. But 【gallant】 suggests spirited and dashing or ornate and florid expressions of courtesy.

【Chivalrous】 suggests high-minded, disinterested, sometimes self-sacrificing attentions.