I’ll answer the first part of your question “What is verbal abuse?”
Verbal abuse is unwarranted and often unprovoked words, whether spoken or written, whose intent is to damage, belittle, intimidate, humiliate or embarrass the target, or to otherwise make the person feel or appear to be “less”.
So things such as taunts, name-calling, spreading lies (or even damaging truths) in a malicious way, even if it is sometimes accompanied by a helping of “it’s for your own good” can all be verbal abuse. Sometimes teasing is just teasing; after all, friends and loving family members sometimes do some of these things at selected times. We all have our failings and embarrassing moments from the past, and sometimes a friend or family member will gleefully point that out to someone who doesn’t know that story about you that is being told. On the other hand, threats of bodily harm to you or loved ones, and obviously mean-spirited jabs are pretty easy to spot.
Only you can judge when “teasing” crosses a line into “abuse”. Sometimes the abuse goes on long enough, or subtly enough, that you start to believe that you really are “less” or “less worthy” than others, even though objectively you try to behave and follow the rules and get along. That’s why sometimes, if you missed the point at which “teasing” turned into “abuse” and “controlling”, then it might take a real friend or another outsider to say, “You deserve better than that,” and help you either develop better coping strategies or to get away from the abuser.
Having said all of that, it’s impossible to say that anything your father has said to you in the little bit that you’ve shown us is “abuse”. I would tend to think not. It’s not uncommon for parents to not believe things that their kids say, especially if there’s a history of untruthfulness. (That’s why it’s absolutely imperative that you develop a reputation for telling the truth, even when it hurts you sometimes. If people know from experience that you always tell the truth, then you get the benefit of these kinds of doubts.) And your father hasn’t threatened to hurt you; he’s merely holding a threat of removing some electronic toys from you in order to get you to do something he wants. This is an ancient parental custom, probably as old as our species – in my day it was television and transistor radios that were withheld for noncompliance with the ‘rents.
From what you’ve said in the response to @Dog, your parents are trying to help you to grow up and confront people when you need to in order to say “no”. This is an absolutely vital thing for you to be able to do. Your life may will depend on it someday. I’m 100% in favor of what your dad is doing, even if I’m not absolutely certain that he’s doing it the right way.