great, large

Quick Summary

Prefixes are key morphemes in English vocabulary that begin words. The origin of the prefix mega- is an ancient Greek word which meant “large.” This prefix appears in a somewhat “large” number of “large” English vocabulary words, such as megaphone, megahit, and megabyte. An easy way to remember that the prefix mega- means “large” is through the word megastore, which is simply a store that is very “large” in floor area.

Omega, Oh My!

Prefixes are key morphemes in English vocabulary that begin words. I hope that today’s podcast on the prefix mega- will be a megahit, and so live “large” in your mind!

The word mega is often used by itself simply to mean something that is “large.” A megaphone makes someone’s voice sound “large” or very loud. You might find a megaphone for sale at a megastore, or very “large” store. In turn, such a megastore might be located in a megalopolis, or very “large” city or collection of cities which form one “large” urban area. Speaking of constructions, everyone has seen Stonehenge, which is made up of very “large” stones called megaliths.

Have you ever taken a megadose of megavitamins? If so, that would be a very “large” dose of some very “large” amounts of vitamins!

A computer “byte” consists of just enough memory or storage to encode a single character, such as an “a” or “1.” Soon after the kilobyte, or unit of storage of 1000 bytes, came the megabyte, or “large” byte, which consisted of 1,000,000 bytes, a considerably “larger” unit of computer memory! We have long since gone past the megabyte, having forayed into the realms of the gigabyte (one billion bytes) and the terabyte (one trillion bytes). Watch out for the even “larger” petabyte and exabyte!

Lastly, omega is the Greek letter which ended the Greek alphabet. It was the “large” or “long” “O,” in contrast to “omicron,” which was the “small” or “short” letter “o.”

There is no doubt that we’ve gone “big” or “large” with the prefix mega-! We can now be megaprefix megastars because our knowledge of the prefix mega- is so “large!”

  1. megahit: ‘large’ hit or success
  2. mega: ‘large’
  3. megaphone: instrument that makes a ‘large’ sound
  4. megastore: a very ‘large’ store
  5. megalopolis: a very ‘large’ city
  6. megalith: a very ‘large’ stone
  7. megadose: very ‘large’ dose
  8. megavitamin: a ‘large’ amount of vitamins
  9. megabyte: a ‘large’ number of bytes
  10. omega: Greek ‘large’ letter “O”
  11. megastar: a superstar who is even “larger” than other stars


  • megalomania

    Megalomania is the false belief someone has that they are very powerful and have control over other people's lives, a condition that sometimes occurs due to mental illness.

  • megabyte

    a unit of information equal to 1000 kilobytes or 10^6 (1,000,000) bytes

  • megahertz

    one million periods per second

  • megalith

    memorial consisting of a very large stone forming part of a prehistoric structure (especially in western Europe)

  • megalopolis

    a very large urban complex (usually involving several cities and towns)

  • megaphone

    a cone-shaped acoustic device held to the mouth to intensify and direct the human voice

  • megaton

    a measure of explosive power (of an atomic weapon) equal to that of one million tons of TNT

  • omega

    the ending of a series or sequence

Differentiated vocabulary for your students is just a click away.