Prefixes

Master the word beginnings that change meaning and create new words

What Are Prefixes?

Prefixes are word parts added to the beginning of base words to change their meaning or create new words. They are powerful tools for expanding vocabulary and understanding word relationships.

Learning common prefixes helps you decode unfamiliar words and see how English words are built from smaller meaning units.

Common Prefixes

Negative Prefixes

  • un- - unhappy, unfair, unable
  • in- - invisible, incorrect, incomplete
  • im- - impossible, impatient, immature
  • il- - illegal, illogical, illiterate
  • ir- - irregular, irresponsible, irrational

Directional Prefixes

  • re- - return, rewrite, rebuild
  • pre- - preview, prepare, prevent
  • post- - postpone, postwar, postgraduate
  • sub- - subway, submarine, submerge
  • super- - superman, superstar, superhuman

Number & Size Prefixes

  • bi- - bicycle, bilingual, biannual
  • tri- - triangle, tricycle, triple
  • mini- - miniskirt, minivan, minicomputer
  • micro- - microscope, microwave, microchip
  • macro- - macroeconomics, macrocosm, macroscopic

Time & Order Prefixes

  • ante- - antecedent, antedate, anteroom
  • fore- - forecast, foretell, forewarn
  • mid- - midnight, midday, midterm
  • neo- - neonatal, neoclassical, neologism
  • proto- - prototype, protoplasm, protolanguage

How Prefixes Work

Changing Meaning

Prefixes can completely change the meaning of a word:

  • happy + un- = unhappy (not happy)
  • write + re- = rewrite (write again)
  • view + pre- = preview (view before)
  • possible + im- = impossible (not possible)

Creating New Words

Prefixes help create new words by adding specific meanings:

  • co- means "together" (cooperate, coworker, coauthor)
  • anti- means "against" (antibiotic, antisocial, antifreeze)
  • auto- means "self" (automatic, autobiography, automobile)
  • trans- means "across" (transport, transfer, translate)

Interactive Quizzes

Quiz 1: Identify the Prefix

Question: What prefix is in "unhappy" and what does it do?

Show Answer

The prefix is un-. It changes the meaning from "happy" to "not happy" or "unhappy."

Quiz 2: Create New Words

Question: Add the prefix re- to "write" and explain what the new word means.

Show Answer

Adding re- to "write" creates rewrite, which means "to write again" or "to write in a different way."

Quiz 3: Prefix Meanings

Question: What does the prefix pre- mean? Give three examples.

Show Answer

The prefix pre- means "before." Examples: preview (view before), prepare (make ready before), prevent (stop before it happens).

Quiz 4: Opposite Meanings

Question: What prefix would you add to "visible" to make it mean "not visible"?

Show Answer

You would add the prefix in- to create invisible, which means "not visible" or "unable to be seen."

Notes Section

Spelling Changes: Some prefixes change spelling when added to certain words (e.g., "in-" becomes "im-" before words starting with "p" or "b").

Multiple Prefixes: Words can have multiple prefixes (e.g., "unprecedented" has both un- and pre-).

Origin: Many English prefixes come from Latin and Greek, which is why they appear in academic and scientific vocabulary.

Pro Tip

When you see an unfamiliar word, try removing the prefix to see if you recognize the base word. This can help you understand the word's meaning.