Also, sick in bed. Ill and confined to bed, as in I was laid up for a week with the flu, or Sally can't come outside; she's sick in bed. [Mid-1500s]
Put in a safe place, as in The ship was laid up in dock with engine trouble, or The hikers were laid up in a cave during the storm. [Mid-1600s] Also see under lay in; lay someone low.
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