Greetings! A rip off can mean several things depending on context. In its literal meaning, to "rip" is to tear apart or split. By adding "off" it means to tear it apart. Example: "He ripped off his sleeves." "Rip off" is also a slang for when someone commits a fraud or any type of exploit to steal from others, an example is overpriced items. Example: "That store ripped off costumers by selling their items twice the real value!" Hope this helped!

You can refer to anything that you bought with a price higher than the usual as 'rip-off',specially when the seller sets the high price when they are sure that you don't know this business at all. For example, you go to a electronic store to buy a computer, if you don't know anything about computers, sellers will usually offer you a higher price, you can call this 'a rip-off' Hope my answers is what you want. And welcome native speakers weigh in to correct me. Thank you.

Definition of rip-off cheat,defraud,cheat A.to copy or imitate blatantly or unscrupulously B.to perform,achieve or score quickly or easily <the teens ripped off the store where they had been working for the summer> <the thief ripped off some jewelry as soon as no one was looking>

Most commonly it is when the price of something is unfairly high. eg "This bottle of water cost 15 euros. What a rip-off!" (this is the the sense it is mostly used. it can be a noun. which it is in this case of a verb (to rip someone off) The actual meaning of the verb is used but it usually suggests something is being actually torn. "They ripped off each others clothing" (this is quite common as well, and we say it to describe getting undressed, or undressing someone else very forcefully and passionately) "She ripped off a page from the notepad"

Most commonly I hear people say "I got ripped off" which mean they feel cheated or or defrauded, or they feel that someone has stolen something from them.