Sentence:  At this moment, Giulietta, who had already <WSD>forslept</WSD> and digested the virtue of the potion, awoke and feeling herself kissed, misdoubted her that the friar, being come to take her up and carry her to his chamber, [...] 
Meaning of the word marked with <WSD> tags:  To neglect through sleep or by sleeping; sleep through; oversleep; sleep off.