The Meaning of COB: What It Is and How To Use It

Do you know the definition of COB? This article will provide you with all of the information you need on the abbreviation COB, including its definition, usage, and more!

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What does the abbreviation COB stand for?

According to Hub Spot, the term COB stands for close of business. This refers to the end of financial markets in EST, which define the US business hours. This is used in business communications to communicate deadlines and refers to the time 5:00PM EST. Using COB is different from EOD because COB specifically refers to an eastern time zone. If a company has an LA office and an NY office, an employee needs to know if it is the end of their day or the end of the day on the other side of the country. This is similar to the terms EOB (end of business), end of day (EOD), end of play (EOP), and close of play (COP). If a colleague said they needed something by COB Friday, this would mean 5PM Eastern Standard Time on Friday, at the end of the business day.

Per Dictionary, the word cob can also be simply used as a word. This word has a variety of different meanings, including a corncob of kernels of maize, male swan, or a thick-set, short-legged stout horse that has a high gait and is used for driving. In the British English Midlands, it is used to refer to a rounded mass or lump, or some building material that is a mixture of clay and straw. A cob is also a Spanish-American coin from the 16th-18th centuries. It was made of crude silver or gold, had a characteristically irregular shape and bore only a partial impression of the dies from which it was struck. A cob is also a black-backed gull, Larus marinus, and an adobe cottage.

A cob loaf can also refer to a round loaf of bread, and the word cob is informal British meaning a punishment consisting of blows to the buttocks, as well an an archaic slang term for a spider. This likely comes from the Icelandic kobbi seal, but is ultimately of uncertain origin and may have alternative etymologies like the cognate of Icelandic kubba or German kübel meaning large container. We may never know the exact origins of cob. This is not to be confused with cobb, which is a type of salad as is a chop. The pronunciation of cob is kɒb. 

According to The Free Dictionary, the term COB can stand for much more than close of business. This term has a plethora of other potential definitions and shorthand meanings. However, these are less common. If you do decide to use one of these alternate definitions, make sure that you provide the proper context so the other person is not confused.

  •  Current on Board
  •  Combined Operations Building (Canada)
  •  Cash on the Barrelhead
  •  Chairman of the Board
  •  Continuously Overwhelmed with Blessings
  •  Conan O’Brien (TV personality)
  •  California-Oregon Border
  •  City of Beaverton (Oregon)
  •  Commencement of Business
  •  Continent Ocean Boundary
  •  Cobol Source Code
  •  Civilians on the Battlefield
  •  Colegio Oficial de Biólogos (Spanish: Association of Biologists)
  •  Coordination Of Benefits (health insurance plans and health insurance policies, i.e. COBRA (Consolidated Omnibus Budget Reconciliation Act of 1985 per CMS), Medicare, insurance company, Medicaid services and coverage)
  •  Côte d’Opale Basket (French basketball club)
  •  Commission on Biotechnology (International Union of Pure and Applied Chemistry)
  •  Cavalcade of Bands (sanctioning body)
  •  Commission des Operations de Bourse (French stock market regulator)
  •  City of Berkeley (California)
  •  Continuous Open Bidding (sorority/fraternity recruitment)
  •  Carry on Business (license; India)
  •  Company of Biologists (Canada)
  •  Chamber Orchestra of Boston (Massachusetts)
  •  Collocated Operating Base
  •  Chief of the Boat (US Navy)
  •  Copy of Bill
  •  Cost of Borrowing (loan financing)
  •  Contractors on the Battlefield
  •  Chrome Over Brass (snare drums)
  •  Call Out Bonus
  •  Case of Beer
  •  College of the Bahamas
  •  Comitê Olímpico Brasileiro (Brazilian Olympic Committee)
  •  Council of Bureaux (International Association of National Motor Insurers’ Bureaux)
  •  Crude Oil Boiler (petrochemicals manufacturing)
  •  Crip or Blood
  •  Circle of Bosses
  •  Church of the Brethren
  •  Change of Beneficiary
  •  Close of Business
  •  Council Of Brothers (gaming clan)
  •  Church Office Building (Church of Jesus Christ of Latter-day Saints)
  •  Crotchety Old Bitch
  •  Certificate in Online Business
  •  Concluding Observation (United Nations)
  •  Center of Balance (measurement)
  •  City of Baltimore (Baltimore, MD)
  •  Children of Bodom (band; Finland)
  •  Class of Business
  •  Come on Baby (game)
  •  Change of Basis (linear algebra, changing vectors from one basis to another)
  •  Center for Oral Biology (Karolinska Institute; Huddinge, Sweden)
  •  Conformity Assessment Body
  •  Conduct of Business
  •  College of Business
  •  City of Bellingham (Washington)
  •  Command Operating Budget
  •  Combined Order of Battle
  •  Communications Office Building (NASA)
  •  Cut Out Background (digital photo manipulation)
  •  California Orange Bud (marijuana)
  •  Chris O’Brien (musician)
  •  City of Bones (novel)
  •  Country of Birth
  •  Contingency Operating Base
  •  City of Brownsville (Texas)
  •  Center of Battery (US DoD)
  •  Commercial Online Banking
  •  Crazy Old Bastard
  •  Citizen Oversight Board
  •  Crew-Overboard
  •  Career Opportunities Bulletin (various organizations)
  •  Control Output Buffer
  •  Commander of Brothers (gaming community)
  •  Community of Believers (various organizations)
  •  Clear-Over-Base (2-component car paints)
  •  Carry Over Balance (finance)
  •  CONUS Operating Base
  •  City of Brass (game)
  •  Clean on Board (shipping)
  •  Cost Of Business
  •  Confirmation of Benefits (insurance)
  •  Crusty Old Bastard
  •  Center of Buoyancy (physics)
  •  Continuity of Business
  •  Cheap Old Bastard
  •  Clothing Optional Beach
  •  Cranky Old Bastard
  •  Cargo Onboard
  •  Chip On Board
  •  COBOL Source Code (file name extension)
  •  Certificate of Birth
  •  Central Obrera Boliviana (Bolivian labor organization)
  •  Corn, Oats, & Barley (livestock feed)
  •  Coalition of Brothers (gaming community)
  •  Cash over Billionaires (band)
  •  Cost of Billing
  •  Club Olympique Briochin (French sports club; est. 1947)
  •  Capital One Bank
  •  City of Bridgetown (Barbados)
  •  Chimie Organique et Bioorganique (French: Organic Chemistry and Biochemistry)
  •  Call On Business

Overall, the acronym COB means close of business. The word cob has many different meanings and an unclear word origin.


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