left turn

Short definition from Wiktionary

Noun

1. 1
   An unexpected change from the way things seemed to be going.
2. 2
   Used other than figuratively or idiomatically: see left, turn.

Interjection

1. 1
   A command to a soldier or other person who is marching: turn ninety degrees to your left!

Verb

1. 1
   To turn ninety degrees to one's left, especially in response to a military command while marching.