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

More than two decades after Treadwell and Huguenard were killed, their deaths remain among the most infamous bear attacks on record and recently spawned yet another documentary, Diary Of The Grizzly Man. —Johnny Dodd, PEOPLE, 22 Dec. 2025

While the stadium was beloved by fans, age and structure caught up to the Metrodome, which saw multiple roof collapses, including the infamous one in 2010. —Rashad Alexander december 22, Kansas City Star, 22 Dec. 2025

Not to be left out of the taxing-raising orgy, the special interests in the city of Los Angeles exploited the Upland decision to pass the infamous Measure ULA tax, a massive increase in the city’s real estate transfer tax on the sale of properties valued over $5 million. —Jon Coupal, Oc Register, 21 Dec. 2025

The story lodged in the memories of why people don’t step up to help others in distress is an infamous 1964 murder case. —Jen Christensen, CNN Money, 20 Dec. 2025

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