Years building an out-of-the way nest (5)
I believe the answer is:
teens
'years' is the definition.
(I have seen 'Adolescent years' mean 'teens' so perhaps 'years' could also mean 'teens')
'an out-of-the way nest' is the wordplay.
'an out of' indicates anagramming the letters.
'the way' becomes 'e' (Compass direction - East).
'e'+'nest'='enest'
'enest' anagrammed gives 'TEENS'.
'building' acts as a link.
(Other definitions for teens that I've seen before include "13-19 age group" , "Adolescent years" , "Years 13-19" , "seven-year period" , "The years 13 to 19" .)