Sentence:  The water-nymphs, that in the bottom played, / Held up their pearled wrists, and took her in, / Bearing her straight to aged Nereus' hall; / Who, piteous of her woes, reared her <WSD>lank</WSD> head, / And gave her to his daughters to imbathe ... 
Meaning of the word marked with <WSD> tags:  Languid; drooping, slack.