Alright for a Greek character to have an animal (5)
I believe the answer is:
Here is my best explanation:
'an animal' is the definition.
(I've seen this before)
'alright for a greek character' is the subsidiary indication.
'alright' becomes 'ok' ('OK' can be a synonym of 'alright').
'for' means one lot of letters go next to another.
'greek character' becomes 'pi'.
'to have' is the link.
(Other definitions for okapi that I've seen before include "Giraffe family mammal", "Beast related to giraffe", "African animal related to the giraffe", "Horned ruminant", "Wild animal", "African relative of the giraffe", "Type of giraffe", "Animal related to giraffe", "Giraffe relative" and "Small giraffe".)