African islander organised galas in spring month (8)
I believe the answer is:
malagasy
'african islander' is the definition.
(I've seen this before)
'organised galas in spring month' is the wordplay.
'organised' indicates an anagram.
'in' means one lot of letters goes inside another.
'spring month' becomes 'may' (May is a spring month).
'galas' anagrammed gives 'lagas'.
'lagas' going into 'may' is 'MALAGASY'.
(Other definitions for malagasy that I've seen before include "Asian" , "old African republic" , "language" , "African islander" .)