The Collaborative International Dictionary of English v.0.48:

Omnipresent \Om`ni*pres"ent\, a. [Omni- + present: cf. F.
   omnipr['e]sent.]
   Present in all places at the same time; ubiquitous; as, the
   omnipresent Jehovah. --Prior.
   [1913 Webster]

WordNet (r) 3.0 (2006):

omnipresent
    adj 1: being present everywhere at once [syn: omnipresent,
           ubiquitous]

Moby Thesaurus II by Grady Ward, 1.0:

94 Moby Thesaurus words for "omnipresent":
   absolute, all-embracing, all-encompassing, all-knowing, all-out,
   all-pervading, all-powerful, all-present, all-seeing, all-wise,
   allover, almighty, born, boundless, broad-based, changeless, clean,
   clear, comprehensive, congenital, consummate, creating, creative,
   deep-dyed, downright, dyed-in-the-wool, egregious, endless,
   eternal, eternally the same, everlasting, everywhere, exhaustive,
   glorious, good, hallowed, highest, holy, immeasurable, immortal,
   immutable, infinite, intensive, just, limitless, loving, luminous,
   majestic, making, merciful, numinous, omnibus, omnipotent,
   omniscient, one, out-and-out, outright, perfect, permanent,
   perpetual, pervasive, plain, plumb, pure, radiant, radical,
   regular, sacred, shaping, sheer, sovereign, straight, supreme,
   sweeping, thorough, thoroughgoing, through-and-through, timeless,
   total, ubiquitous, unbounded, unchanging, unconditional, undefined,
   unending, universal, unlimited, unmitigated, unqualified,
   unreserved, unrestricted, utter, veritable, wholesale