modus operandi

American  

[moh-duhs op-uh-ran-dee, -dahy, moh-doos oh-pe-rahn-dee] / ˈmoʊ dəs ˌɒp əˈræn di, -daɪ, ˈmoʊ dus ˌoʊ pɛˈrɑn di /

noun

plural

modi operandi

1. a mode of operating or working.

   The aim of a scientist is to investigate the modus operandi of the natural world.

2. one’s usual way of doing something: MO

   A criminal’s modus operandi can give the police a lead.

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modus operandi British  

/ -ˈrændaɪ, ˈməʊdəs ˌɒpəˈrændiː /

noun

1. procedure; method of operating

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modus operandi Cultural  

1. The way someone does something; a characteristic method: “Her modus operandi in buying a new car always included a month of research.” This phrase, often abbreviated “m.o.,” is used by police to describe a criminal's characteristic way of committing a crime. From Latin, meaning “method of operation.”

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Etymology

Origin of modus operandi

First recorded in 1645–55; New Latin: literally “mode of working”

Example Sentences

“Given the modus operandi of this market is to shoot first and ask questions later, we believe this selloff represents an attractive buying opportunity,” Monness, Crespi, Hardt analyst Brian White wrote on Tuesday.

From Barron's • Mar. 3, 2026

Other digital asset treasury companies that sought to ape Saylor’s modus operandi have suffered a similar fate.

From MarketWatch • Feb. 5, 2026

His modus operandi generally is better understood when he is so considered.

From The Wall Street Journal • Dec. 18, 2025

Authorities then discovered that other monks had similarly transferred money to Ms Golf - which police called her "modus operandi".

From BBC • Jul. 16, 2025

Which was largely true and seemed to establish the modus operandi for the rest of my horse-riding life.

From This Side of Wild by Gary Paulsen

Related Words

• rule of thumb