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1. To measure up to in kind or quality
   - come, amount
    
2. Determine the sum of
   "add up all the people in this town to those of the neighbouring town";
   - total, tot, tot up, sum, sum up, summate, tote up, add, add together, tally
    
3. Add up in number or quantity
   "The bill added up to $2,000";
   - total, number, come, amount
    
4. Be reasonable, logical or comprehensible
   - make sense

Derived forms: adds up, added up, adding up

Type of: be, become, count, enumerate, number, numerate, turn