Definition of affair noun from the Oxford Advanced American Dictionary

Oxford3000

affair

noun
/əˈfɛr/
 
 

public/political activities

1 affairs [plural] events that are of public interest or political importanceworld/international/business affairsan expert on foreign affairs (= political events in other countries)affairs of state

event

2 [countable, usually singular] an event that people are talking about or describing in a particular wayThe newspapers exaggerated the whole affair wildly.The debate was a pretty disappointing affair.She wanted the celebration to be a simple family affair.

relationship

3 [countable] a sexual relationship between two people, usually when one or both of them is married to someone elseShe is having an affair with her boss. see also love affair

private business

4 affairs [plural] matters connected with a person's private business and financial situationI took care of my father's financial affairs.She wanted to put her affairs in order before she died.5 [singular] a thing that someone is responsible for (and that other people should not be concerned with) synonym businessHow I spend my money is my affair.

object

6 [countable] (old-fashioned) (with an adjective) an object that is unusual or difficult to describeHer hat was an amazing affair with feathers and a huge brim.
IDIOM

a state of affairs

a situation, usually a bad one
This state of affairs can no longer be ignored.a state of affairs