noun
Common
FBI
EHF-bee-eye
FBI (noun) means the Federal Bureau of Investigation, the United States' main domestic intelligence and federal law enforcement agency. Example: “The FBI opened an investigation into the fraud case.”
noun
1
The Federal Bureau of Investigation, the United States' main domestic intelligence and federal law enforcement agency.
"The FBI opened an investigation into the fraud case."
"Agents from the FBI raided the warehouse at dawn."
How to use FBI
Learner’s notesIn plain EnglishThe FBI is the U.S. government agency that investigates federal crimes like terrorism, organized crime, cybercrime, and major fraud.
When to use it
Always written in capital letters as an initialism; rarely spoken as a single word.
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The _____ opened an investigation into the fraud case.
Synonyms
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the Bureau
Federal Bureau of Investigation
the Feds
Frequently asked questions
What does “FBI” mean?
The word “FBI” means the Federal Bureau of Investigation, the United States' main domestic intelligence and federal law enforcement agency. In plain terms, the FBI is the U.S. government agency that investigates federal crimes like terrorism, organized crime, cybercrime, and major fraud.
How do you pronounce “FBI”?
“FBI” is pronounced EHF-bee-eye (/ˈɛf.biː.aɪ/ in IPA).
How do you use “FBI” in a sentence?
Here is “FBI” used in a sentence: “The FBI opened an investigation into the fraud case.”
What part of speech is “FBI”?
“FBI” is a noun.
Is “FBI” a common word?
“FBI” is a fairly common word in modern English.
What is the difference between the FBI and the CIA?
The FBI is a domestic agency — it investigates federal crimes and handles security within the United States. The CIA works abroad, gathering foreign intelligence to inform national security. Put simply, the FBI looks inward at law enforcement at home, while the CIA looks outward at intelligence overseas.
What does the FBI do?
The FBI investigates federal crimes such as terrorism, cybercrime, organised crime, public corruption, and kidnapping. It also serves as the country's main domestic intelligence agency, protecting national security. Its agents gather evidence, make arrests, and work with local, state, and international partners on major cases.
What is the difference between the FBI and the police?
Local police enforce state and city laws and respond to everyday crime in their community. The FBI is a national agency that handles federal offences and cases crossing state lines, such as terrorism or large-scale fraud. The two often cooperate, but their authority and scope differ.
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