Adieu: Farewell, good bye
Example: I bade him adieu when he was leaving the country forever.
Aide-de-camp: Camp assistant
Example: A military officer who serves as a personal assistant to a higher-ranking officer.
Aide-mémoire: Memory aid; a note serving as a reminder
Example: In international relations, an aide-mémoire is a proposed agreement or negotiating text circulated informally among delegations for discussion.
Ambiance: The mood, character, quality, tone, atmosphere, etc., particularly of an environment.
Example: The restaurant had a delightful ambiance.
Amour-propre: Self love; self respect
Example: He was essentially a good-tempered man and had not a trace of amour propre in his nature.
Aperitif: Cocktail (The actual meaning of apéritif is ‘to open’ and it has come from Latin originally).
Example: Start the evening by enjoying an aperitif beside the roaring fire in the snug lounge area.
Attaché: Attached; A person assigned to a diplomatic post
Example: Most of the Ambassadors have their attaché to deal with people's queries.
Au contraire: On the contrary
Example: I told you that she misbehaved with me. Au contraire you are scolding me.
Au courant: Up-to-date
Example: The shoes, the hair, the clothes- every last detail of her dress, in fact- was utterly au courant.
Au gratin: With gratings; Anything that is grated and put on top of a dish, like breadcrumbs or cheese
Example: She likes to cook her pasta and grilled vegetables au gratin as her kids like that more.
Bas-relief: Low relief/design; Sculpture that is only slightly more prominent than its background.
Example: The marble bas-relief panels were set into the walls of the hall.
Beau geste: A fine or noble gesture, often futile.
Example: My fellow writers supported me by writing letters of protest to the publisher, but their beau geste could not prevent the inevitable.
Beau monde: High society
Example: Such elegant decor would impress even the beau monde.
Blond / blonde: Fair-haired; blond is for a man and blonde for a woman.
Example: I saw a blonde walking on the beach with a floral printed skirt.
Bon appétit: Good appetite; Enjoy your meal
Example: She invited us for a meal and said bon appétit when we began eating.
Bon mot: A witty remark or comment
Example: One bon mot after another flew out of his mouth, charming the audience.
Bon vivant: A person who lives luxuriously and enjoys good food and drink.
Example: It's true he's quite the bon vivant, but when he gets down to business he conducts himself like a Spartan.
Bon voyage: Have a good trip
Example: Women in India apply vermillion on their husband's foreheads as a custom to bid bon voyage when they go on journeys.
Bonjour : Good Morning. (also used in the afternoon)
Example: Looking forward to speaking with you all soon, bonjour!
Brunette: Small, dark-haired female; The French word ‘brun’, dark-haired, is what English really means by ‘brunette’
Example: Ms Franklin, a stunning brunette, is serving four years for drugs offenses in a Texas jail.
Carte blanche: Unrestricted power to act on one's own.
Example: I may have carte blanche around the office, but at home I'm a slave to my family's demands.