1. most polite, respectful, and gracious in manner; showing the highest degree of courtesy
Usage: superlative form of courtly

Examples

• He was the courtliest gentleman at the formal dinner.
• The ambassador's courtliest behavior impressed all the foreign dignitaries.
• Even in difficult situations, she maintained her courtliest demeanor.
• The courtliest knights were known for their impeccable manners.
• His courtliest speech won over the skeptical audience.
• The butler's courtliest service made every guest feel welcome.