Geographical relocation of the heron (5)
I believe the answer is:
rhone
'geographical relocation' is the definition.
Although both the answer and definition are singular nouns, I can't see how one could define the other.
'of the heron' is the wordplay.
'of' indicates an anagram (the answer comes from or \'of\' the letters).
'heron' is an anagram of 'RHONE'.
Can you help me to learn more?
(Other definitions for rhone that I've seen before include "wine-producing area" , "French river from Alps to Mediterranean" , "French wine region" , "Camargue river" , "River at Lyons" .)