To put together to make a total (3,2)
I believe the answer is:
tot up
'a total' is the definition.
(thesaurus)
'to put together to make' is the wordplay.
'to put together' means one lot of letters go next to another.
'make' becomes 'tup' (I can't explain this - if you can you should give a lot more credence to this answer).
'to'+'tup' is 'TOT UP'.
Can you help me to learn more?
(Other definitions for tot up that I've seen before include "Summate" , "Sum - total" , "Determine the sum of" , "Do summer job" , "Tally" .)