Not what you'd expect from a tot (3)
I believe the answer is:
rum
'tot' is the definition.
Although both the answer and definition are singular nouns, I cannot see how one could define the other.
I don't understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for rum that I've seen before include "Strange drink from molasses" , "Sugar-cane product" , "Alcoholic drink from molasses" , "Odd sort of spirit used in grog" , "Odd, like sailor's drink" .)