Pronunciation: (chēf'tun, -tin), [key]
1. the chief of a clan or a tribe.
2. a leader of a group, band, etc.: the robbers' chieftain.
3. (cap.) Mil.Britain's main battle tank since 1969, fitted with a 120mm gun and two machine guns and weighing 55 tons (50 m tons).
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.