Green’s Dictionary of Slang

P-38 n.

(US) an attractive female.

[US]Chicago Trib. Graphic Section 26 Dec. 7/1: Jive Talk [...] Smooth Girl Slick chick. Sweet stuff. Wolf bait. Queen of hearts. P-38. Able Grable. A good deal. A doll. Smooth potato. Hot gingerbread. Pretty pigeon. 20-20 little squab.