Heading for Spain, possibly get a tan and be inactive (8)
I believe the answer is:
stagnate
'be inactive' is the definition.
(I've seen this before)
'heading for spain possibly get a tan' is the wordplay.
'heading for' suggests taking the first letters.
'possibly' indicates anagramming the letters.
The first letter of 'spain' is 's'.
'get'+'a'+'tan'='getatan'
'getatan' is an anagram of 'tagnate'.
's'+'tagnate'='STAGNATE'
'and' acts as a link.
(Other definitions for stagnate that I've seen before include "Be idle" , "Become dull through inactivity" , "decline" , "(Of water) become motionless" , "Cease to flow or move" .)