From Longman Dictionary of Contemporary Englishcast off phrasal verb1 TTWto untie the rope that fastens your boat to the shore so that you can sail away2 GET RID OF cast somebody/something ↔ off literary to remove or get rid of something or someone that you no longer want or need His family had cast him off without a penny.3 DLHto finish a piece of knitting by removing the stitches from the needle to make an edge that will not come undonecast something ↔ off Cast off four stitches. → cast→ See Verb tablecast-offˈcast-off adjective [only before noun] CLOTHEScast-off clothes or other goods are not wanted or have been thrown away
Examples from the Corpus
cast-off• Tomorrow Hari would go to Ma Popits first thing and see what cast-off clothing she could buy for young Will.• It was a cast-off fireman's jacket he was wearing.• According to tradition, Mattia entered the convent chapel, cut off her hair, and donned a cast-off habit.• One such offer was from a theme park in Dogpatch, Arkansas, which is devoted to cast-off metal monuments.• Then she sees Rainbow's cast-off shirt at the foot of the stairs, tangled in a heap with Anya's jeans.