in action

1. Engaged in some activity. I think it's important to for students to see different businesses in action, so they get a sense of how things work when they leave school. I had never seen her in action before! Wow, she is truly a gifted singer. A: "Oh, sorry, I didn't realize you were in action." B: "No, it's fine, I need to take a break from painting anyway. What's up?"

2. Having resumed a previous activity, especially after illness or injury. I need to take today off to deal with this cold, but I should be back in action on Monday. He took time out from his basketball career to try his hand at baseball, but he'll back in action on the courts this season. I've been in bed with the flu for nearly a week now, but I'm hoping to be back in action tomorrow.

in ˈaction

working, operating, etc.; doing a particular activity: John’s a great cook — you should see him in action.

in action

1. mod. healthy and getting around. After I got well, I was in action again immediately.

2. mod. selling or using drugs. (Drugs.) In this neighborhood, somebody is in action twenty-four hours a day.