It's not at all clear in Bermuda (3)

I believe the answer is:
mud
'it's not at all clear' is the definition.
I can't tell whether this definition defines the answer.
'in bermuda' is the wordplay.
'in' says the answer is hidden in the clue.
'MUD' is hidden in the letters of 'bermuda'.
Can you help me to learn more?
(Other definitions for mud that I've seen before include "-, -, Glorious - (Flanders and Swann)" , "Earth and water mixed" , "Liquid earth" , "slander" , "soft soil" .)
