infamous

adjective

in·​fa·​mous ˈin-fə-məs 

1

: having a reputation of the worst kind : notoriously evil

an infamous traitor

2

: causing or bringing infamy : disgraceful

an infamous crime

3

: convicted of an offense (as a felony) bringing infamy

infamously adverb

Frequently Asked Questions

Is being infamous always a bad thing?

Infamous has a small range of meanings, and none of them are ones that most people would care to be described with. It may mean "notoriously evil," "disgraceful," or "convicted of an offense bringing infamy" (infamy is "evil reputation brought about by something grossly criminal, shocking, or brutal").

Is infamous the opposite of famous?

Infamous is not the opposite of famous. It does not mean "not famous" or "exceptionally famous." It means "having a reputation of the worst kind." Although the in- prefix often indicates negation or gives a meaning opposite to the word it is attached to, it occasionally will have other meanings, such as "inward" and "thoroughly."

What is the difference between unfamous and infamous?

Although it would appear that both of these words are created by adding a similar prefix to the word famous, they actually have quite different meanings. Infamous means "notoriously evil," whereas unfamous simply means "not famous." Infamous is by far the more commonly-used of the two.

Synonyms of infamous

• notorious

Examples of infamous in a Sentence

The most infamous of South America's poisonous snakes are the ringed coral snake and the pit viper. —Candice Millard, The River of Doubt, 2005

Clemens is famous, or maybe infamous, for his brushback pitches and in particular for his penchant for "doubling up," throwing two brushbacks in a row. —Pat Jordan, New York Times Magazine, 4 Mar. 2001

Instead we invoke the infamous dark matter, also known to make up most of the mass of other galaxies (both spiral and elliptical), clusters of galaxies, and the universe. What is it? Your guess may not be quite as good as mine, but almost. —Virginia Trimble et al., Sky & Telescope, January 1995

a city infamous for poverty and crime

He committed an infamous crime.

Recent Examples on the Web

The show is based on the now-infamous case of Erin Patterson, the Australian woman who was convicted on multiple counts of murder and attempted murder after allegedly preparing food for guests containing toxic death cap mushrooms. — Joe Otterson, Variety, 28 Oct. 2026

This bacterial illness is infamous for the explosive killing spree known as the Black Death, which wiped out between a third and half of the population of Europe between 1347 and 1353. — Faye Flam, Scientific American, 27 Oct. 2026

Also among the Golden Dawn initiates was infamous occultist Aleister Crowley, who the documentary said was a destructive force in the group, binging on drugs while being accused of summoning demons using Golden Dawn rituals. — Adam Harrington, CBS News, 27 Oct. 2026

Concerns over fatal accidents involving children helped turn public opinion against the infamous experiment, which Congress repealed within the year. — Lila Hempel-Edgers, Chicago Tribune, 27 Oct. 2026

Word History

Etymology

Middle English, from Latin infamis, from in- + fama fame

First Known Use

14th century, in the meaning defined at sense 1

Kids Definition

infamous

adjective

in·​fa·​mous ˈin-fə-məs 

1

: having an evil reputation

an infamous traitor

2

: causing or bringing an evil reputation : detestable

an infamous crime

infamously adverb

Legal Definition

infamous

adjective

in·​fa·​mous ˈin-fə-məs 

: of, relating to, or being a crime punishable by imprisonment (as a year or more in a penitentiary) that can lead to loss of rights and privileges upon conviction

also : convicted of such a crime