Mo means modus operandi or mode of operation, which is defined as the way something is done.(abbreviation)
An example of a mo is a person putting on both of their socks before putting on their shoes.
See mo in Webster's New World College Dictionary
Origin: L modus operandimode of operation
Origin: < ending of L abl. forms of ordinals, after prep. in, as in duodecimo (< duodecimus, twelfth)
See mo in American Heritage Dictionary 4
Origin: From (duodeci)mo.
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