"Wren" is a term to describe a number of mutually unrelated passerine birds. They are all small, curious, skulking birds that fly only when pressed, preferring to hide away in thick vegetation when they feel threatened.

The families Troglodytidae (true wrens), Acanthisittidae (New Zealand "wrens"), Maluridae (Australasian "wrens") and Acanthizidae (scrubwrens, heathwrens and fernwren) all contain species called "wrens".