Add up as well as down (3)

I believe the answer is:

tot

I believe this clue is a double definition.

'add' is the first definition.
(synonyms)

'up as well as down' is the second definition.

(Other definitions for tot that I've seen before include "Rum measure" , "Tiny child" , "Add up, aggregate" , "Add - youngster - dram" , "Child's" .)

I've seen this clue in The Times.

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