orderof magnitude

order of magnitude n. pl. orders of magnitude

1. An estimate of size or magnitude expressed as a power of ten:

Earth's mass is of the order of magnitude of 10²² tons; that of the sun is 10²⁷ tons.

2. A range of values between a designated lower value and an upper value ten times as large:

The masses of Earth and the sun differ by five orders of magnitude.

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