Affair may refer to professional, personal, or public business matters or to a particular business or private activity of a temporary duration, as in family affair, a private affair, or a romantic affair.
Political affair may refer to the illicit or scandalous activities of public, such as the Watergate affair

Watergate scandal

The Watergate scandal was a political scandal during the 1970s in the United States resulting from the break-in of the Democratic National Committee headquarters at the Watergate office complex in Washington, D.C., and the Nixon administration's attempted cover-up of its involvement...

, or to a legally constituted government department, for example, the United Nations Department of Political Affairs

United Nations Department of Political Affairs

The United Nations Department of Political Affairs is a department of the Secretariat of the United Nations with responsibility for monitoring and assessing global political developments and advising and assisting the United Nations Secretary General and his envoys in the peaceful prevention and...

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A romantic affair, also called an affair of the heart, may refer to sexual liaisons among unwed parties, or to various forms of nonmonogamy

Forms of nonmonogamy

Non-monogamy is a blanket term which covers several types of interpersonal relationships in which an individual forms multiple and simultaneous sexual and/or romantic bonds. This can be contrasted with its opposite, monogamy, and yet may arise from the same psychology...

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