I identify ship that's certainly not shipshape (2,1,4)
I believe the answer is:
in a mess
'i' is the definition.
Both the answer and definition are singular nouns.
Perhaps you can see a link between them that I don't see?
I cannot understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for in a mess that I've seen before include "Tucker here for Tommy" , "at sixes and sevens" .)