Flair means "natural talent," "aptitude," "bent," "knack," or "keen perception": "This mechanic has a flair for spotting engine troubles." "She lived in Europe for many years, developing her flair for languages." Flare applies to a sudden burst of flame or the act of flaming: "His quick temper flared at the insult." "The guide used a flare to show me the way to our camp."
Dictionary of problem words and expressions. Harry Shaw. 1975.