cheap shot

Noun cheap shot has 2 senses

• cheap shot(n = noun.communication) - an unnecessarily aggressive and unfair remark directed at a defenseless person;
is a kind of barb, dig, gibe, jibe, shaft, shot, slam

• cheap shot(n = noun.act) - an illegal and unsportsmanlike act of unnecessary violence; "he called a penalty on them when the lineman took a cheap shot at the quarterback"
is a kind of shot