In Science (physics, electronics, biology, mathematics, chemistry and other sciences):

• Carrier wave, a waveform suitable for modulation by an information-bearing signal
• Charge carrier, an unbound particle carrying an electric charge
• a mathematical Set over which a Boolean algebra is defined.
• Carrier-protein, a protein that facilitates the transport of another molecule
• a Catalyst or other intermediary in a chemical reaction
• Asymptomatic carrier, an organism infected with an infectious disease agent, but displaying no symptoms
• Genetic carrier, an organism that has inherited a genetic trait or mutation, but displaying no symptoms
• Chloroorganic carrier, a group of molecules that facilitates the transport of dyes into a fiber
• an inert substance co-packaged with an active pharmaceutical drug
• Carrier (disease) in medicine.
• Gestational carrier, a surrogate mother

'''Technology:

• Carrier recovery in telecommunications
• Lathe carrier, a device that transfers motion to a workpiece
• NO CARRIER, a text message transmitted by a modem to a computer to indicate that it is not, or no longer, connected to a remote party.
• Carrier, a multiprotocol instant messenger.

Ethnography and geography:

• Carrier is the English name for the Dakelh, an indigenous First Nations people of British Columbia, Canada
• Carrier language, the Athabaskan language of the Dakelh people
• Carrier, Oklahoma, a town in Garfield County, Oklahoma, United States
• The Carrier Dome, a multi-sport, domed athletic facility in Syracuse, New York, named for the Carrier Corporation.

Commerce:

• Wireless carrier, an organization that operates a wireless network for mobile phones
• Common carrier, an organization that transports a product or service using its facilities, or those of other carriers, and offers its services to the general public
• Carrier Corporation, the air conditioning and commercial refrigeration manufacturing division of United Technologies, named after its founder, Willis Carrier
• Carrier (telephony, networking), A term used to refer to various telephone companies that provide local, long distance or value added services. A system or systems whereby many channels of electrical information can be carried over a single transmission path
• CARRIERS-interconnect, software company that offers products and solutions for worldwide telecommunication businesses
• Mail carrier, a postal worker

Entertainment:

• Carrier (video game), a video game for the Sega Dreamcast play system
• Carrier Command, a simulator game for Amiga and many other platforms
• Carrier (game), a South Pacific World War II board game from Victory Games
• Carrier (documentary), a ten-part documentary miniseries that aired on PBS in April 2008
• Carrier, a Protoss capital ship and fighter platform in the StarCraft science-fiction series.
• The Carrier, the enormous living interdimensional spaceship home to the Authority, a team of comic superheroes
• Carriers, a 1998 film
• Helicarrier, a flying aircraft carrier from the Marvel Comics.

Other:

• Aircraft carrier, a type of warship
• an informal abbreviation of carrier bag