Sentence:  The girl threw back her head and laughed merrily. "You poor young man," she cried; "put that way it does sound alarming." Then she grew serious again. "There's plenty of time for you to <WSD>back out</WSD> now if you like. Just call the waiter, and ask for my bill. We'll say good-bye, and the incident will finish." 
Meaning of the word marked with <WSD> tags:  To withdraw from something one has agreed to do.