Stone chucked by a canoeist hit islands in the Pacific (7)
I believe the answer is:
oceania
'islands in the pacific' is the definition.
(continent in the Pacific)
'stone chucked by a canoeist hit' is the wordplay.
'stone' becomes 'st'.
'chucked by' is a deletion indicator (deleted letters are chucked away).
'hit' indicates anagramming the letters.
'a'+'canoeist'='acanoeist'
'acanoeist' with 'st' removed is 'acanoei'.
'acanoei' anagrammed gives 'OCEANIA'.
(Other definitions for oceania that I've seen before include "Pacific islands region" , "Large South Pacific region" , "Pacific Ocean area" , "Pacific island region" , "Orwell depicted at war" .)