What does the prefix per- mean?
Per- comes from the Latin per, which means "through" or "completely". It shows that something goes through from side to side, or that it is done all the way.
ESEN
Prefix · through / completely / intensively
per-
Signals through, completely, or with intensity: perfect, permanent, persist, pervade, persuade.
Literary
Written by Bryan López, English teacher · Updated
Per- as an intensifier
Many times per- works as a booster: it adds the sense of "totally" or "thoroughly" to the base word. That is why it names things that are done or felt completely, down to the deepest level. The idea of going through or completing is always present, and it helps you guess the meaning of words you do not know.
How it is used
Attaches to nouns, adjectives, and verbs:
- per- + completeness/intensityfect → perfectmanent → permanentsist → persistvade → pervademeate → permeate
- per- + complete transformationvert → pervertplex → perplexturb → perturbsuade → persuadeceive → perceive
Pronunciation: /pɜːr/. Different from "pre-" (before) and "pro-" (in favour of).
How it is pronounced
per-/pɜːr/
Tap the button to hear how the prefix sounds. Each word in the table has its own audio.
Examples
Root word
With per-
In a phrase
- fectperfectA score of ten out of ten is considered a perfect result.
- manentpermanentThe tattoo is permanent and can only be removed by laser treatment.
- sistpersistDespite three failures, she persisted until she achieved a breakthrough.
- vadepervadeA sense of unease pervaded the room when the results were announced.
- suadepersuadeHe spent an hour trying to persuade her to consider studying medicine.
- plexperplexThe missing file perplexed the IT team — no one could explain it.
- meatepermeateThe smell of fresh coffee permeated the whole office in minutes.
Common mistakes
"perfect" as an adjective and as a verb are different words
"perfect" works as both an adjective and a verb in English, but the stress shifts depending on the grammatical role
As an adjective: "PER-fect" (stress on first syllable) = having no flaws. As a verb: "per-FECT" (stress on second syllable) = to make flawless or improve until perfect. "She has a perfect score" (adj) vs "She is perfecting her technique" (verb). This stress-shift pattern is common in two-syllable English words.
persuade = force someone to do something
persuade = convince someone through arguments, reasons, or appeals — not through force
"Persuade" means to convince through reasons, arguments, or emotional appeal: "She persuaded him by explaining all the benefits." If force is used, it is "coercion" ("coerce," "force," "compel"), not persuasion. Persuasion respects the other person's will; coercion overrides it.
A trick to remember it
Picture something passing all the way through: per- = through, completely. perfect (thoroughly made), permanent (staying through time).
Practise what you learned
Exercise 1 · Form the word
Exercise 2 · Pick the right one
"Despite three consecutive failures, she continued to ___ with her research until finally achieving a breakthrough."
Exercise 3 · Pick the right one
How does the pronunciation of "perfect" change when used as an adjective versus a verb?
Frequently asked questions
What does the prefix per- mean in English?
The prefix per- signals through, completely, or with intensity: perfect, permanent, persist, pervade, persuade.
How do you pronounce per-?
The prefix per- is pronounced /pɜːr/. For example, "perfect".
Can you give an example of a word with per-?
"fect" becomes "perfect". It is a typical example of the per- prefix.
Other useful prefixes
circum-
Signals around or surrounding something: circumference, circumstance, circumnavigate, circumspect.
pro-
Signals support for something or forward movement: progress, promote, provide, pro-democracy.
trans-
Signals crossing, transformation, or movement through: transport, transform, translate, transfer.
Learn every English prefix
un-, re-, pre-, dis-, over-, in-... every beginning you need to unlock thousands of English words at once.