about-turn
noun /əˌbaʊt ˈtɜːn/
  /əˌbaʊt ˈtɜːrn/
 (British English) (also about-face North American English, British English)
 [singular]- a complete change of opinion, plan or behaviour- The government did an about-turn over nuclear energy.
 Word Originlate 19th cent. (originally as a military command): shortening of right about turn.