round down(redirected from round a number down)
To use a lower or the next-lowest number, especially so as to eliminate decimal places. (Usually done when the non-whole number is less than .5; higher than that, and the number would typically be rounded up.) A noun or pronoun can be used between "round" and "down." Most stores round their prices down to .99 instead of keeping them as whole numbers. The accountant had been using the exact numbers from the sales data, while I had been rounding them down when doing my own calculations.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
round something down
to reduce a fractional part of a number to the next lowest whole number. (See also round off to something.) You can round this figure down if you want. It won't affect the total all that much. Please round down all figures having fractions less than one-half.
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.