1. omni-- : word-forming element meaning "all," from Latin omni-, combining form of omnis "all, every, the whole, of every kind," of unknown origin, perhaps literally "abundant," from *op-ni-, from PIE root *op- (1) "to work, produce in abundance" (see opus).

※supplementary words :

(1) omnidirectional : (adj.) 1927, from omni- + directional (see direction).

(2) omnivore : (n.) 1890, formed from omni- on model of carnivore (see omnivorous).

(3) omnisexual : (adj.) by 1959, from omni- + sexual. Earliest application is to Walt Whitman.
(4) omniscience : (n.) 1610s, from Medieval Latin omniscientia "all-knowledge," from Latin omnis "all" (see omni-) + scientia "knowledge" (see science).
(5) omnipresence : (n.) c. 1600, from Medieval Latin omnipraesentia, from omnipraesens, from Latin omnis "all, every" (see omni-) + praesens "present."
(6) omnium gatherum : (n.) 1520s, "miscellaneous collection," humorous coinage from Latin omnium "of all" (genitive plural of omnis; see omni-) + Latinized form of English gather.
(7) omnivorous : (adj.) 1650s, from Latin omnivorus "all-devouring," from omnis "all" (see omni-) + vorare "devour, swallow" (see voracity). Related: Omnivorously; omnivorousness.
(8) omnifarious : (adj.) 1650s, from Late Latin omnifarius "of all sorts," from Latin omnifariam "on all places or parts," from omnis "all" (see omni-) + -fariam "parts" (compare multifarious). Related: Omnifariously; omnifariousness.
(9) omnibus : (n.) 1829, "four-wheeled public vehicle with seats for passengers," from French (voiture) omnibus "(carriage) for all, common (conveyance)," from Latin omnibus "for all," dative plural of omnis "all" (see omni-). Introduced by Jacques Lafitte in Paris in 1819 or '20, in London from 1829. In reference to legislation, the word is recorded from 1842. Meaning "man or boy who assists a waiter at a restaurant" is attested from 1888 (compare busboy). As an adjective in English from 1842.
(10) omnipotent : (adj.) early 14c., from Old French omnipotent "almighty, all-powerful" (11c.) or directly from Latin omnipotentem (nominative omnipotens) "all-powerful, almighty," from omnis "all" (see omni-) + potens (genitive potentis) "powerful" (see potent). Strictly only of God or a deity; general sense of "having absolute power or authority" is attested from 1590s.