rounded

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mathematics Rounding off numbers involves the termination of a string of digits at some incomplete point, but, unlike truncating, taking into account the digits beyond that point. It is well illustrated with the simple fraction ⅔ = 0.666 6~ with the digit 6 occurring endlessly. To terminate as shown is merely to truncate; to write the number as 0.666 7, which is the closest value at four decimal places to the real value of the fraction, is to have it rounded.

Some form of termination, i.e. rounding else truncation, must be induced for all decimal fractions that do not terminate naturally, which is true for all irrational numbers as well as many rational numbers. All non-terminating rational numbers fall into a repeating pattern (shorter in digit count than the value of the denominator), so they can be expressed by terminating at the completion of the first pattern, then indicating its repetition by putting a dot above the first and last digits of the pattern (which is a single digit in the above case). But naturally terminating numbers must often be shortened to fit circumstances, e.g. ¹/₁₆ = 0.0625 (exactly) may have to be entered into a column that allows for only three decimal places. In such circumstances there are two numbers equally close to the true value; to avoid an undue overall bias, the convention is to end the rounded value with an even digit, 0.062 in this case.

adjective

Deviating from a straight line: arced, arched, arciform, bent, bowed, curved, curvilinear. See straight/bent.

• Phonetics - rounded: (adj) designating speech sound pronounced with rounded lips