The "Female" tank was a variation of the British heavy tank deployed during the First World War. It carried multiple machine guns instead of the mix of machine guns and cannons mounted on the "male" tank. Lieutenant-Colonel Ernest Swinton, who played a part in the development of the first British tank and who was co-creator of the term "tank" (originally a code word), is credited with inventing these gender-related terms, thinking that the best tank tactics would have the two types operating in concert.