SAT PREFIX

Mastering prefixes is a "cheat code" for the SAT Reading and Writing section. Instead of memorizing thousands of individual words, you can decode the meaning of unfamiliar vocabulary by breaking them down.

Here are the most common prefixes found on the SAT, categorized by their meaning.

1. Opposites & Negatives (The "Not" Group)

These are the most frequent prefixes. They turn a word into its opposite.

Prefix

Meaning

Examples

A-, An-

Without, lacking

Amoral, atypical, anarchy

Anti-

Against, opposite

Antipathy, antithesis, antibody

Contra-, Counter-

Against

Contradict, counteract, controversy

De-

Down, away from, undoing

Denounce, deplete, decry

Dis-

Not, apart

Disparate, discordant, ingenuous

In-, Im-, Il-, Ir-

Not

Inevitable, impeccable, illicit, irreverent

Mis-

Bad, wrong

Misnomer, misconception

Non-

Not

Nonchalant, nonentity

Un-

Not

Unwitting, unconventional

2. Quantity & Size

These help you determine the scale or number of what is being discussed.

Prefix

Meaning

Examples

Ambi-

Both

Ambivalent, ambiguous

Equi-

Equal

Equitable, equivocate

Macro-

Large

Macrocosm

Micro-

Small

Microcosm, microscopic

Mono-

One

Monotonous, monopoly

Multi-

Many

Multifaceted, multifarious

Omni-

All

Omniscient, omnipresent

Poly-

Many

Polyglot, polyphonic

3. Direction & Position

SAT passages often use these to describe relationships between ideas or physical placement.

Prefix

Meaning

Examples

Ab-

Away from

Abstain, abhor, abnormal

Ad-

Toward

Advocate, adhere, adjoin

Circum-

Around

Circumspect, circumvent

Ex-

Out, away

Exacerbate, exclude, extricate

Inter-

Between

Intervene, intermediate

Intra-

Within

Introspective, intravenous

Per-

Through, thoroughly

Pervasive, permeable

Pre-

Before

Precursor, precocious

Post-

After

Posthumous, posterity

Sub-

Under, below

Subvert, substantive

Super-

Above, beyond

Superfluous, supersede

Trans-

Across

Transient, transgression

4. Quality & Tone

These prefixes usually indicate whether a word has a positive or negative "charge."

Prefix

Meaning

Examples

Bene-

Good, well

Benefactor, benevolent

Mal-

Bad, evil

Malevolent, malicious, malign

Eu-

Good, pleasant

Euphemism, eulogy, euphoria

Pro-Tip for the SAT

When you encounter a word you don't know, use the "Slash and Burn" method:

  1. Slash the prefix off the word.

  2. Identify the root meaning.

  3. Burn (eliminate) answer choices that don't match the positive/negative charge of the prefix.

Example: If you see "Irreproachable," you know ir- means "not." If you know "reproach" is related to "blame," the word means "not able to be blamed" (perfect).

Would you like me to give you a few practice sentences where you can try decoding words using these prefixes?