add; add together; add up; aggregate; amount; amount of money; center; centre; core; essence; gist; heart; heart and soul; inwardness; join; kernel; marrow; meat; nitty-gritty; nub; pith; substance; sum of money; sum total; sum up; summarise; summarize; summate; summation; tally; tot; tot up; total; totality; tote up; union;