omni

all; every

Spelled omni · omnis 'all, every'

Latin omnis meant all: an omniscient narrator knows everything, an omnipotent being has all power, and an omnibus gathers works into one volume.

Words built from it

omniscient — knowing everything
Latin omni- (all) + scient- (knowing, from scire 'know') → omniscient
omnipotent — having unlimited power
Latin omni- (all) + potens (powerful) → omnipotens → omnipotent
omnipresent — present everywhere
Latin omni- (all) + praesens (present) → Medieval Latin omnipraesens → omnipresent
omnivorous — eating both plants and animals; also, eagerly taking in many kinds of things
Latin omni- (all) + vorare (devour) → omnivorus + English -ous → omnivorous
omnibus — a collection of previously separate works in one volume; also, covering many items
Latin omnis (all) → omnibus (for all) → omnibus
omnidirectional — operating or extending in all directions
omni- (all) + directional (relating to direction) → omnidirectional

insomniac — From insomnia, built from Latin in- 'not' and somnus 'sleep'; the letters omni occur within the word but do not mean 'all.'