South African facilities for captive animals, might you say? (4)

I believe the answer is:

zulu

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'south african' is the definition.
(I've seen this in another clue)

I don't understand the remainder of the clue.

(Other definitions for zulu that I've seen before include "1964 film about the Battle of Rorke's Drift" , "Final letter heard on radio" , "Communications code for Z" , "SE African people, Shaka their founder" , "Member of a people of southeast Africa" .)

I've seen this clue in The Independent.

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