Unusually nice lad in charge of N Atlantic island (9)
I believe the answer is:
icelandic
'atlantic island' is the definition.
Although both the answer and definition are singular nouns, I can't see how one could define the other.
'unusually nice lad in charge of' is the wordplay.
'unusually' indicates an anagram.
'in charge of' becomes 'ic'.
'nice'+'lad'='nicelad'
'nicelad' is an anagram of 'iceland'.
'iceland'+'ic'='ICELANDIC'
'n' is the link.
Can you help me to learn more?
(Other definitions for icelandic that I've seen before include "Eg, native to Reykjavik" , "Language of people of Reykjavik" , "As European" , "in island republic" , "Like many sagas" .)