if sb is laid up, they are unable to work, etc. because of an illness or injury; if you lay up problems or trouble for yourself, you do sth that will cause you problems later
lay sb up
if sb is laid up, they are unable to work, etc. because of an illness or injury
She's laid up with a broken leg.
lay sth up
if you lay up problems or trouble for yourself, you do sth that will cause you problems later
lay sth up
to stop using a ship or other vehicle while it is being repaired
lay sth in / up
to collect and store sth to use in the future
to lay in food supplies
Definitions from the Oxford Advanced Learner's Dictionary, 9th edition