'registered' definitions:

Definition of 'registered'

(from WordNet)
adjective
(of animals) officially recorded with or certified by a recognized breed association; especially in a stud book; "a registered Percheron" [ant: unregistered]
adjective
Listed or recorded officially; "record is made of `registered mail' at each point on its route to assure safe delivery"; "registered bonds" [ant: unregistered]
adjective
(of a boat or vessel) furnished with necessary official documents specifying ownership etc

Synonyms of 'registered'

From: Moby Thesaurus