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

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

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What does the abbreviation MB mean?

According to Chron, Cyber Definitions, and Urban Dictionary, the term MB can refer to either the internet slang term “my bad,” or the computing term megabyte. My bad is used when someone has made a mistake and they are expressing the mistake to another person. This is usually a small mistake. Someone will use MB in casual settings, such as via SMS text message or on social media if there was a mix-up or small mistake made. This shorthand term should be avoided in formal or professional settings like letters and business emails, or in situations where a large mistake was made that requires a greater apology than a slang term.  

A megabyte is a measure of information storage capacity that is used in computing. One MB is equal to 1000 KB, or kilobytes. One megabyte is 1 million bytes. This term is also commonly abbreviated as “meg” in speech. Be careful – this term must be uppercase and capitalized as MB. Otherwise, if one were to use Mb, this would refer to a megabit, or MBIT, which is equal to one eighth of a megabyte. One megabyte is equal to eight megabits. Other storage sizes include a mebibyte (MIB), a gigabyte (GB), gigabit, or gibibyte (GIB), as well as kibibytes. The mega prefix denotes that it is equal to one million bytes. Other metric prefixes or binary prefixes for file sizes include tera, giga, and kilo. A megabyte of data is surprisingly small in the modern day, and a CPU can parse these with ease. This international system of units is used across the globe to refer to a unit of information for file sizes for video, audio, MP3, and other file types. Someone might refer to MBPS, which stands for megabytes per second when referring to download speeds or connection speed, or they could refer to the MB of mobile data that they are charged data usage fees on. Sometimes a file size will change due to compression. 

According to The Free Dictionary, the acronym MB can stand for much more than just megabytes or “my bad.” This abbreviation has a plethora of other definitions. While these alternate definitions are still valid, they are far less common and should be used sparingly. If you do decide to use one of these alternate terms, make sure that you provide the reader with the proper context so that they can infer the correct intended meaning and are not confused. You should make this a habit with all acronyms that have more than one meaning. Try using flashcards or making bookmarks to learn all of these different meanings!

  •  Molecular Biology
  •  Medicine Bow (Camp Yawgoog, BSA)
  •  Missile Bomber
  •  Marine Biology (various schools)
  •  Mavis Beacon (typing tutor program)
  •  Multibacillary (leprosy)
  •  Mel Brooks (director)
  •  Middle Babylonian
  •  Military Base
  •  Mixed-Resin Bed (anion & cation)
  •  Mikrobitti (Finnish computer magazine)
  •  Message Back
  •  Monmouth Beach (New Jersey)
  •  Machine Batch
  •  Mission Baptiste (French)
  •  Memory Backup (SONET)
  •  Multistage Bayesian
  •  Motherboard
  •  Mixed Breed
  •  Marginal Benefit
  •  Manaetic Behemoth (gaming)
  •  Measured Business
  •  Marine Base
  •  Managed Backup (remote computer file backup)
  •  Main Battery
  •  Mixed Bed
  •  Manhattan Beach
  •  Marine Barracks
  •  Manitoba, Canada
  •  Moon Bounce (ham radio)
  •  Municipal Bank PLC
  •  Milton Bradley
  •  Mass-Balance
  •  Message Broadcasting (Tandem)
  •  Myrtle Beach
  •  Megabit
  •  Marker Beacon
  •  Muy Bien
  •  Mean Bias
  •  Message Board
  •  Management Board
  •  Maintenance Branch
  •  Malibu Beach
  •  Merit Badge (Boy Scouts of America)
  •  Memory Buffer
  •  Motorboat
  •  Measurement Base
  •  Mythbusters
  •  Medium Bomber
  •  MacBook
  •  Magic Burst (Final Fantasy XI gaming)
  •  Moody Blues (band)
  •  Mechanical Breaking
  •  Manufacturing Base
  •  Michelle Branch
  •  Ministerieel Besluit (Dutch: Ministerial Deree; Belgium)
  •  Mystery Block
  •  Multibanco (Portugal)
  •  Middle Button (computer mouse)
  •  Muslim Brotherhood
  •  Michel Beroff (classical pianist)
  •  Metric Buttload
  •  Marine Battalion
  •  Manufacturers Bank (California)
  •  Mario’s Bakery
  •  Miami Beach (Florida)
  •  Mercedes-Benz
  •  Musquodoboit Batholith
  •  Maintain Benefits
  •  Manned Base
  •  Military Budget
  •  MacBeth
  •  Martinique
  •  Mindless Behavior
  •  Milton Bradley Company
  •  Mana Break (gaming)
  •  Manaburn (Everquest skill)
  •  Mario Brothers (game)
  •  Millibar
  •  Moon Bandit (computer game)
  •  Melt-Banana (band)
  •  Willys-Overland 1/4-Ton 4×4 Truck (WWII Jeep)
  •  Methyl Bromide (fumigant)
  •  Masterblasters (gaming clan)
  •  Military Battalion
  •  Medicine Box
  •  Minimum Bid (auctions)
  •  Motorbike
  •  Master Bedroom
  •  Mechanized Brigade
  •  Maybe
  •  Military Brat
  •  Main Base
  •  Moscow Bound (Vietnam POWs)
  •  Meccanica Breganzese (bucket crusher manufacturer; Italy)
  •  Monza e Della Brianza (Italian province)
  •  Mossbauer Spectrometer (NASA)
  •  Macro Block
  •  Mortgage Broker (various companies)
  •  Multi-Ball (pinball)
  •  Matchbox
  •  Modified By
  •  Mike Bibby (NBA Player)
  •  Missile Battalion
  •  Military Bank
  •  Manila Bulletin
  •  Machine Basin
  •  Manic Bloom (band)
  •  Message Blocking
  •  Maintenance Burden
  •  Ministerstvo Bezopasnosti (Russian Security Ministry)
  •  Mennonite Brethren
  •  Melli Bank PLC
  •  Marching Band
  •  Mineralolie Brancheforeningen
  •  Mainboard (UK)
  •  Magnetic Bearing
  •  Magazijnbeheerder (Dutch)
  •  Machinery Breakdown (insurance)
  •  Monthly Balance
  •  Medicinae Baccalaureus (Bachelor of Medicine)
  •  Monster Box
  •  Muppet Babies (cartoon)
  •  Media Bureau (Federal Communications Commission)
  •  Myoglobin
  •  Milan Baros (soccer player)
  •  Mesiobuccal (tooth anatomy)
  •  MusicBrainz (open source music-database)
  •  Main Beam
  •  Make Buy

How can the abbreviation MB be used in a sentence?

MB can be used in many different circumstances to mean either my bad or megabytes. The abbreviation MB is used in the following dialogs as examples.

Son: Dad, are you on your way? Practice was over 30 minutes ago.

Dad: Shoot, MB. I thought you guys ended at 4:45, not 4:15. OMW now, be there in 5.

Here, the dad uses MB to mean “my bad.” He mixed up the time that practice ended. 

Dad: Can you do a speed test on your internet? I’m trying to tell the internet company that our MB per second upload speed is super slow.

Son: Sure!

Overall, the acronym MB usually stands for either my bad or megabyte. These different terms will be indicated depending on the topic at hand, as well as the other definitions of MB. 


  1. MB – What does MB stand for? | The Free Dictionary 
  2. MB | What Does MB Mean? | Cyber Definitions 
  3. Mb | Urban Dictionary 
  4. What Does MB Mean for Storage on a Website? | Chron