Adjective has 3 senses

• registered(a = adj.all) - (of animals) officially recorded with or certified by a recognized breed association; especially in a stud book; "a registered Percheron"

Antonym: unregistered

• registered(a = adj.all) - listed or recorded officially; "record is made of `registered mail' at each point on its route to assure safe delivery"; "registered bonds"

Antonym: unregistered

• registered(s = adj.all) - (of a boat or vessel) furnished with necessary official documents specifying ownership etc;