affair

(noun) a vaguely specified concern. Synonyms: matter, thing. Examples: "Several matters to attend to." "It is none of your affair." "Things are going well."

(noun) a usually secretive or illicit sexual relationship. Synonyms: affaire, intimacy, liaison, involvement, amour.

(noun) a vaguely specified social event. Synonyms: occasion, social occasion, function, social function. Examples: "The party was quite an affair." "An occasion arranged to honor the president." "A seemingly endless round of social functions."