Oceanic bird (6)
(Other definitions for guillemot that I've seen before include "Diving bird" , "cliff-ledge nester" , "Diver" , "An auk" , "Seabird" .)
'oceanic bird' is the definition.
(albatross is a kind of oceanic bird)
This is the entire clue.
(Other definitions for albatross that I've seen before include "Coleridge's marine bird." , "High-flyer" , "Large seabird or constant burdan" , "Large oceanic bird" , "golfing term" .)
'oceanic bird' is the definition.
(I know that petrel is a type of oceanic bird)
This is all the clue.
(Other definitions for petrel that I've seen before include "Storm bird" , "Small seabird" , "Seabird sounds like fuel" , "Mother Carey's chicken" , "Seabird that flies far from land" .)