Test quirky uniform in zoo, initially (4)
I believe the answer is:
quiz
'test' is the definition.
(I know that test can be written as quiz)
'quirky uniform in zoo initially' is the wordplay.
'initially' indicates taking the first letters.
The initial letters of 'quirky uniform in zoo' is 'QUIZ'.
(Other definitions for quiz that I've seen before include "General knowledge contest" , "Series of testing questions" , "popular in many pubs" , "Q-and-A entertainment" , "Test consisting of short questions" .)