Jumbo — the plane that's seen all over (8)
I believe the answer is:
elephant
'jumbo' is the definition.
(Jumbo was an elephant who lived in London Zoo)
'the plane that's seen all over' is the wordplay.
'the plane' anagrams to 'ELEPHANT'.
Though, I am not sure how the anagram is indicated.
Can you help me to learn more?
(Other definitions for elephant that I've seen before include "Source of ivory" , "Get this animal from Pat and Helen" , "Large animal found in the plane?" , "Large pachyderm" , "Huge mammal" .)