The statement is said to express ire and/or contempt. When someone says it, they are saying that the person who used the aforementioned adjective should not be using it, as they don't truly know what it means to feel it. I.E. you had your face melted off, and you broke the arm of someone who pissed you off. You would say "Painful? You don't know the meaning of the word."
Offender: My family are all idiots. I mean, I'm never stop having to suffer their genocide.
You: Suffering? you don't know the meaning of the word.
Can be a nice person but is mostly so self absorbed that she hurts everybody around her without knowing or excepting that she is doing so. She can be spiteful and hateful out of her own pains and usually doesn't care what other people think. She can also be someone to watch out for when it comes to your bf, she wants what she cant have and when she does have it she breaks it like an old toy. Beware or Melanias