A viscount ( /ˈvaɪkaʊnt/ "vie-count", for male) or viscountess (for female) is a member of the European nobility whose comital title ranks usually, as in the British peerage, above a baron, below an earl (in the United Kingdom) or a count (the earl's continental equivalent).

The word viscount, known to be used in English since 1387, comes from Old French visconte (modern French: vicomte), itself from Medieval Latin vicecomitem, accusative of vicecomes, from Late Latin vice- "deputy" + Latin comes (originally "companion; later Roman imperial courtier or trusted appointee, ultimately count).

As a rank in British peerage, it was first recorded in 1440, when John Beaumont was created Viscount Beaumont by King Henry VI. The word viscount corresponds in the UK to the Anglo-Saxon shire reeve (root of the non-nobiliary, royal-appointed office of sheriff). Thus early viscounts were originally normally given their titles by the monarch, not hereditary; but soon they too tended to establish hereditary principalities lato sensu (in the wider sense).