A drop of tea ~n right? (4)
I believe the answer is:
tear
'a drop' is the definition.
(teardrop)
'tea n right?' is the wordplay.
'n right?' becomes 'r' (I can't explain this - if you can you should give a lot more credence to this answer).
'tea'+'r'='TEAR'
'of' is the link.
Can you help me to learn more?
(Other definitions for tear that I've seen before include "Shred" , "Split - career" , "charge" , "Rip, pull apart" , "'A rip, binge or drop of saline solution (4)'" .)