Half of cons stayed in this Spanish seaside location (5)
I believe the answer is:
costa
'this spanish seaside location' is the definition.
Although both the answer and definition are singular nouns, I can't understand how they can define each other.
'half of cons stayed' is the wordplay.
'half of' means to take half the letters.
'stayed' becomes 'sta' (I am not sure about this - if you are sure you should believe this answer much more).
'cons' halved is 'co'.
'co'+'sta'='COSTA'
'in' is the link.
Can you help me to learn more?
(Other definitions for costa that I've seen before include "A Spanish coast, perhaps del Sol" , "Coast (anag.)" , "Rib (Botany, Zoology)" , "and 5 Down: Spanish holiday destination" , "A Spanish coastal region, perhaps del Sol" .)