epi-

prefix

variants or ep-
1
: upon
epiphyte
: besides
epiphenomenon
: attached to
epididymis
: over
epicenter
: outer
epiblast
: after
epigenesis
2
a
: chemical entity related to (such) another
epimer
b
: chemical entity distinguished from (such) another by having a bridge connection
epichlorohydrin

Word History

Etymology

Latin, from Greek, from epi on, at, besides, after; akin to Old English eofot crime

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Cite this Entry

“Epi-.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/epi-. Accessed 4 Feb. 2026.

Kids Definition

epi-

prefix
: over : upon
epiphyte
Etymology

derived from Greek epi "on, at"

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