order of magnitude (
http://definr.com/order of magnitude)
n 1: a degree in a continuum of size or quantity; "it was on the
order of a mile"; "an explosion of a low order of
magnitude" [syn:
order]
2: a number assigned to the ratio of two quantities; two
quantities are of the same order of magnitude if one is
less than 10 times as large as the other; the number of
magnitudes that the quantities differ is specified to
within a power of 10 [syn:
magnitude]