A girl who is otherwise calm and cool-headed, but when sexually aroused turns into a freak. The term comes from the fact that Sodium, a chemical element in the Alkali family, violently reacts with water.
Tom: How was that girl last night? She seemed pretty boring.
Bob: She may have seemed boring, but she turned out to be a sodium girl.
Tom: What's a sodium girl?
Bob: When you get her wet, she explodes!
Bob: She may have seemed boring, but she turned out to be a sodium girl.
Tom: What's a sodium girl?
Bob: When you get her wet, she explodes!
by Dudemanfellabra July 14, 2009