do a 180

1. Literally, to begin moving in the opposite direction. (If one physically turns 180 degrees, one will then be facing the opposite direction.) I was going to go to the park, but when I saw those dark clouds roll in, I did a 180 and headed back home. Once I realized I was going the wrong way, I did a 180 at the next light. When I saw Mary in the hallway, I did a 180 and went back the way I came.

2. To make a big change in one's position, opinion, lifestyle, etc. A: "Can you believe that Sam quit his job at the firm?" B: "No, he really did a 180 on being a paralegal!" After a huge public outcry about the controversial program, the president quickly did a 180 and announced that he would not support the plan. The tech giant typically has unyielding success, but they did a major 180 with the disastrous unveiling of their latest gadget.

do a 180 degree turn

To make a big change in some area of one's life. If one physically turns 180 degrees, one will then be facing the opposite direction. A: "Can you believe that Sam quit his job at the firm?" B: "No, he really did a 180 degree turn on being a paralegal!" After a huge public outcry about the controversial program, the president quickly did a 180 turn and announced that he would not support the plan. The tech giant typically has unyielding success, but they did a major 180 turn with the disastrous unveiling of their latest gadget.

turn 180 degrees

1. Literally, to turn and face the opposite direction. I was going to go to the park, but when I saw those dark clouds roll in, I turned 180 degrees and headed back home.

2. To make a big change in one's position, opinion, lifestyle, etc. A: "Can you believe that Sam quit his job at the firm?" B: "No, he really turned 180 degrees on being a paralegal!"