Sort of spots around middle of neck (7)
I believe the answer is:
species
'sort' is the definition.
(species is a kind of sort)
'spots around middle of neck' is the wordplay.
'spots' becomes 'spies' ('spy' can be a synonym of 'spot'**).
'around' means one lot of letters goes inside another.
'middle of' says to take the centre.
The central letters of 'neck' are 'ec'.
'spies' enclosing 'ec' is 'SPECIES'.
'of' is the link.
(Other definitions for species that I've seen before include "Kind, sort" , "Variety, taxonomic group" , "Category" , "Biological grouping" , "Taxonomic grouping" .)