Second story was old (5)
I believe the answer is:
stale
'old' is the definition.
(similar in meaning)
'second story' is the wordplay.
'second' becomes 's' (common abbreviation).
'story' becomes 'tale' (synonyms).
's'+'tale'='STALE'
'was' is the link.
(Other definitions for stale that I've seen before include "Musty or hackneyed" , "piss" , "Boring" , "Lacking freshness" , "past the sell-by date" .)