Modulo (jargon)

The word modulo (Latin, with respect to a modulus of ___) is the Latin ablative of which itself means "a small measure." It was introduced into mathematics in the book Disquisitiones Arithmeticae by Carl Friedrich Gauss in 1801. Ever since, however, "modulo" has gained many meanings, some exact and some imprecise. Generally, to say:

means

Using Gauss's definition

to mean

However, the word modulo has acquired several related definitions with time, many of which have become integrated into popular mathematical jargon.

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