Sentence:  She wanted to see what the <WSD>passion pit</WSD> was all about, but I took her to supper and to "South Pacific" in Memphis rather than to "Dragstrip Girl" at our drive-in. Anyway, rumor had it that she'd already been to the <WSD>passion pit</WSD>. 
Meaning of the word marked with <WSD> tags:  A drive-in theatre, with particular reference to it as a place of intimacy.