pot shot

1. Literally, a shot fired easily or recklessly. The phrase comes from hunting (in which shots ideally yield food for one's pot). You boys can't just take pot shots at any creature you see—there are rules we have to follow out here! Why did you fire a pot shot like that and betray our position to the enemy?

2. By extension, a reckless or careless remark directed at a vulnerable person. Now that everyone knows I was involved in that scandal, the reporters love taking pot shots at me.