It's bound to fall when a thing gets broken (5)
I believe the answer is:
night
'it's bound to fall' is the definition.
I can't tell whether this definition defines the answer.
'a thing gets broken' is the wordplay.
'gets broken' is an anagram indicator.
'thing' is an anagram of 'NIGHT'.
'when' is the link.
Can you help me to learn more?
(Other definitions for night that I've seen before include "Period of darkness" , "See 1 Across" , "That's when it's darkest" , "What proverbially follows day" , "A Hard Day's (the Beatles)" .)