mega-

especially before a vowel, meg-.

1. variant of megalo- (megalith ); also the initial element in units of measure that are equal to one million of the units denoted by the base word (megahertz ). M

mega-

¹

combining form

1. M. denoting 10 ⁶

   megawatt

2. (in computer technology) denoting 2 ²⁰ (1 048 576)

   megabyte

3. large or great

   megalith

4. informal,  great in importance or amount

   megastar

mega

²

/ ˈmɛɡə /

adjective

1. slang,  extremely good, great, or successful

mega–

1. A prefix that means:

2. Large, as in megadose, a large dose.

3. One million, as in megahertz, one million hertz.

4. 2 ²⁰ (that is, 1,048,576), which is the power of 2 closest to a million, as in megabyte.

Word History and Origins

Origin of mega–¹

Combining form representing Greek mégas large, great

Word History and Origins

Origin of mega–¹

from Greek megas huge, powerful

Origin of mega–²

C20: probably independent use of _mega-

Example Sentences

Department of Transportation’s Mega Grant Program for major, complex projects.

From Los Angeles Times

"Mega councils, with populations of half a million people or more, could be imposed on areas when there's no independent, up-to-date evidence to justify councils of this size, and many large councils created previously are struggling financially."

From BBC

"I remember the bus door opened and we all just looked around at each other and said 'this is actually mega'."

From BBC

Meanwhile, a so-called mega dinghy capable of holding more than 100 people was reportedly sighted in the Channel this week, amid concerns that people smugglers could be using larger boats to illegally transport people.

From BBC

Home Office officials are trying to establish whether the presence of the mega dinghy was a one-off, or if it indicates gangs have started to use bigger boats.

From BBC

Related Words

• commanding 
• grand 
• grandiose 
• imperial 
• magnificent 
• massive 
• monumental 
• noble 
• ominous 
• stately 
• striking 
• towering 

When To Use

What does mega- mean?

Mega- is a combining form used like a prefix meaning “large, great, grand, abnormally large.” It is used in many scientific and medical terms.In science, mega- is specifically used as a prefix in units of measure equaling a factor of “one million.” It’s abbreviation is M. So, a megawatt (MW) is one million watts.Mega- comes from the Greek mégas, meaning “large” or “great.”What are variants of mega-?When combined with words or word elements that begin with a vowel, mega- becomes meg-, as in megohm.Mega- is a variant of megalo- and megal-, as in megalomania and megalopsia. Learn more about their specific applications in our Words That Use articles.