I've come to hate the phrase "child sexual abuse".
It is often used to described abusive or violent sexual behaviour towards children, yet it also legally means any and all "underage" sexual activity, and in my country, it legally means cartoons as well.
It's a term that sounds useful, and at least doesn't say "paedophilia" to describe an action, but it's still deliberately vague enough to mean whatever the speaker wants it to mean, in saying "abuse" without describing in what way the action was or wasn't abusive.