The Idiom Attic - a collection of hundreds of English idioms, each one explained.
See also, a list of phrases that relate in some way to the word military
" About face "
1. A military command to turn when on parade. 2. A change from one’s previous position.
1. Stand to attention! Present arms! About face! 2. Winston Churchill joined parliament as a Conservative and then did an about face and changed to the Liberals, before going about face again and re-joining the Conservatives.