—n.
1 the total amount resulting from the addition of two or more items, facts, ideas, feelings, etc. (the sum of two and three is five; the sum of their objections is this).
2 a particular amount of money (paid a large sum for it).
3 a an arithmetical problem (could not work out the sum). b (esp. pl.) colloq. arithmetic work, esp. at an elementary level (was good at sums).
—v.tr. (summed, summing) find the sum of.
Phrases and idioms:
in sum in brief. summing-up
1 a review of evidence and a direction given by a judge to a jury.
2 a recapitulation of the main points of an argument, case, etc.
sum total = sense
1 of n.
sum up
1 (esp. of a judge) recapitulate or review the evidence in a case etc.
2 form or express an idea of the character of (a person, situation, etc.).
3 collect into or express as a total or whole.
Etymology: ME f. OF summe, somme f. L summa main part, fem. of summus highest
Useful english dictionary. 2012.