calculate

v.

1. To determine, especially by using mathematics

   compute, reckon, determine, enumerate, count, figure out, figure, ascertain, ascertain mathematically, work out, estimate, forecast, rate, weigh, gauge, assess, number, figure up, account, sum up, total, divide, multiply, subtract, add, cipher, tally, cast, dope out*, crunch numbers*; see also count, estimate 1, measure 1, reckon.

2. To determine by reasoning or evaluating

   estimate, judge, gauge, think, think likely; see also anticipate 1, assume 1, estimate 1, 2, guess 1.

calculate refers to the mathematical determination of a quantity, amount, etc. and usually implies the use of higher mathematics to calculate distances in astronomy; compute suggests simpler mathematics and implies a determinable, hence precise, result to compute the volume of a cylinder; estimate implies the judging, usually in advance, of a quantity, cost, etc. and connotes an approximate result to estimate the cost of building a house; reckon, an informal substitute for compute, suggests the use of simple arithmetic such as can be performed mentally to reckon the days before elections