Prefix · good / well / normal
Signals something good, normal, or favorable: euphoria, euthanasia, eulogy, euphemism.
Written by Bryan López, English teacher · Updated
Eu- comes from Greek "eu" (good, well, correct) and signals something good, favorable, or functioning correctly: euphoria = an intense feeling of well-being (eu = well + phoria = carrying/feeling); euthanasia = "good death" in Greek (dignified death without suffering); eulogy = a speech of praise for the deceased (eu = well + logos = word); eureka = the Greek exclamation meaning "I have found it well!" It is the exact antonym of dys- (bad, difficult, abnormal).
In biology: eukaryote = an organism whose cells have a true nucleus (eu = true/good + karyon = nucleus); in ecology: eutrophication = the excessive enrichment of water with nutrients (eu = too well-nourished + troph = food), which paradoxically causes environmental problems. In philosophy: eudaimonia = human flourishing, deep well-being (Aristotle's ethical ideal).
Attaches to philosophical, medical, and scientific nouns. Identical in Spanish and English:
Pronunciation: /juː/. Identical in Spanish and English. The exact antonym of dys- (bad, difficult).
eu-/juː/
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"Euthanasia" (from Greek "eu" = good + "thanatos" = death) = good death. In medical ethics: "euthanasia" = the physician administers the lethal treatment directly. "Assisted suicide" = the physician provides the means (a prescription) but the patient takes the final action themselves. They are legally and ethically distinct in most frameworks.
"Euphemism" (eu- = well + pheme = speech) = good/gentle speech. Examples: "pass away" for "die"; "let go" for "fired"; "collateral damage" for "civilian casualties." A euphemism is a communication strategy — replacing harsh directness with softer language — rather than a rhetorical figure like metaphor.
A trick to remember it
Eu- = "good" or "well": euphoria = an intense feeling of well-being, euthanasia = a good death (without suffering), eulogy = good words about someone, euphemism = gentle words for difficult topics. The exact antonym of dys- (bad). In biology: eukaryote = an organism with a true cell nucleus.
Exercise 1 · Form the word
Exercise 2 · Pick the right one
"The politician used 'collateral damage' as a ___, avoiding the more direct phrase 'civilian deaths.'"
Exercise 3 · Pick the right one
What is the precise difference between "euthanasia" and "assisted suicide" in medical ethics?
The prefix eu- signals something good, normal, or favorable: euphoria, euthanasia, eulogy, euphemism. In Spanish it usually maps to eu-.
The prefix eu- is pronounced /juː/. For example, "euphoria".
"phoria" becomes "euphoria". It is a typical example of the eu- prefix.
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