Rip a sad sign (4)
I believe the answer is:
tear
This might be a double definition.
'rip' is the first definition.
(I know that rip can be written as tear)
'a sad sign' is the second definition.
'tear' can be an answer for 'sign' (I have seen 'Sign of sorrow' mean 'tear' so perhaps 'sign' could also mean 'tear'). I'm not sure about the 'a sad' bit.
Can you help me to learn more?
(Other definitions for tear that I've seen before include "A drop of sadness" , "Shred" , "Lachrymal drop - rip" , "Split - career" , "Droplet from the eye" .)