Having tea overseas is bedlam (5)
I believe the answer is:
chaos
'is bedlam' is the definition.
(I've seen this before)
'having tea overseas' is the wordplay.
I cannot really understand how this works, but
'tea' could be 'cha' (cha is a type of tea) and 'cha' is present in the answer.
'overseas' could be 'os' (abbreviation) and 'os' is present in the answer.
This accounts for all the letters.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for chaos that I've seen before include "Total disorder and confusion" , "confused state" , "disarray" , "Anarchy" , "Pandemonium" .)