Is to touch down in Madagascar, perhaps (6)
I believe the answer is:
island
'madagascar perhaps' is the definition.
(I know that Madagascar is a Island)
'is to touch down' is the wordplay.
'to touch down' becomes 'land' (I've seen this in another clue).
'is'+'land'='ISLAND'
'in' is the link.
(Other definitions for island that I've seen before include "Man, say" , "Easter or Christmas, for example?" , "Water-girt land" , "Boffin, Baffin or Barbados" , "Tasmania, perhaps" .)