What does "give it to" mean?

Punish or reprimand, as in Dad really gave it to Tom for coming in so late. This expression, implying a physical or verbal attack, dates from the late 1500s. Also see give someone hell. In more recent times the expression gave rise to give it to someone straight, meaning “to tell someone something candidly and directly.” For example, I asked the doctor to give it to use straight about Mother's condition.