Goodbye to distant eastern waterhole (8)
I believe the answer is:
farewell
'goodbye' is the definition.
(I've seen this before)
'distant eastern waterhole' is the wordplay.
'distant' becomes 'far' (synonyms).
'eastern' becomes 'e'.
'waterhole' becomes 'well'.
'far'+'e'+'well'='FAREWELL'
'to' acts as a link.
(Other definitions for farewell that I've seen before include "Goodbye, adieu, so long" , "Cape at the southernmost point of Greenland" , "symphony" , "Departure" , "It may be said when 15" .)