The heights around Sedan? (5)
I believe the answer is:
andes
'the heights' is the definition.
Although both the answer and definition are singular nouns, I cannot see how one could define the other.
'around sedan?' is the wordplay.
'around' indicates an anagram.
'sedan' with letters rearranged gives 'ANDES'.
Can you help me to learn more?
(Other definitions for andes that I've seen before include "South American mountains" , "Great S American mountains" , "Danes seen in mountains" , "South American mountain system" , "Danes in S American mountains" .)