eu-

comb. form well, easily.
Etymology: Gk

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combining form

Etymology: Middle English, from Latin, from Greek, from ey, eu, from neuter of eys good; akin to Hittite asus good and perhaps to Sanskrit asti he is — more at is

1.

a. : well : easily

euplastic

— opposed to dys-

b. : good

eudaemon

— opposed to dys-

2.

a. : most typical : true

Euascomycetes

euchromosome

b. : truly

eucoelomate

c. : having a complete life cycle

eu-form

3. : improved derivative of a (specified) substance

eucodeine

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a combining form meaning "good," "well," occurring chiefly in words of Greek origin (eupepsia); in scientific coinages, esp. taxonomic names, it often has the sense "true, genuine" (eukaryote)

[ < Gk, comb. form of eús good (adj.) or eú, eû (neut., used as adv.) well]

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eu-,

prefix. good; well; true, as in eugenic, eucalyptus, eulogy, euphoria, euglobulin.

╂[< Greek eu- < eús good]

Eu (no period),

europium (chemical element).

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comb. form good; well; easily; normal

eupeptic | euphony

Origin:

from Greek eu ‘well’, from eus ‘good’

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eu-, prefix

repr. Gr. εὐ-, combining form of ἐύς good, used in neut. form εὖ as adv. = well. In Gr. the words with this as first element are primarily adjs. (often used as ns., and in many instances giving rise to derivative ns. or vbs.). Of these many are parasynthetic f. ns., as εὔστοµος having a good mouth, f. στόµ-α mouth, εὐσχήµων having a good form, f. σχῆµ-α form. In others the second element is a verbal root or a verbal adj. in -τος; the sense of the compound varies (often in the same word) between active and passive; in those that are active the prefix has the force of ‘well’; in those of passive signification its sense is sometimes ‘well’, more commonly ‘easily’: thus, εὐλαβής ‘taking good hold’, ‘easy to take hold of’, f. λαβ- ‘to take’; εὔπρᾱκτος ‘doing well, prosperous’, ‘easy to do’, f. πρᾱκ- (πρᾱ́σσειν) to do; εὐποίητος well made, f. ποιεῖν to make. In Eng. the prefix occurs almost exclusively in words of Gr. derivation, as eulogy, euphemism, or formed on Gr. elements, as eucalyptus; the few exceptions are terms of mod. scientific classification.

In late L. the u in this prefix when occurring before vowels was consonantized (i.e. became v), and in order to preserve the traditional quantity of the syllable the ē was made long, as in ēvangelium. The derivatives and cognates of evangelium are almost the only words current in Eng. with the ev- form of the prefix; in Fr. it is much more common, being used even in recent formations from Gr. elements.