What question are you answering?:
How is it used?:
David just got himself a trophy wife.
What does it mean?:
Wealthy middle-aged men sometimes suddenly decide to separate/divorce their wives of many years and take up with a much younger woman. That new woman is called a trophy wife. It is often thought that the man is having a mid-life crisis (worried about his virility and so takes up with someone younger to 'prove' he's still got it); meanwhile the woman is usually regarded as being attracted to the man for his wealth.
How did it come to be used this way?:
Trophy wife is a derogatory term - something that looks pretty, but doesn't really do anything.
Trivia/fun facts:
Katie Holmes, Katherine Zeta Jones and Barbera Bush are all trophy wives
