The Collaborative International Dictionary of English v.0.48:

Prominent \Prom"i*nent\, a. [L. prominens, -entis, p. pr. of
   prominere to jut out, to project; pro before, forward +
   minere (in comp.) to jut, project: cf. F. prominent. See
   Imminent, Eminent.]
   [1913 Webster]
   1. Standing out, or projecting, beyond the line surface of
      something; jutting; protuberant; in high relief; as, a
      prominent figure on a vase.
      [1913 Webster]

   2. Hence; Distinctly manifest; likely to attract attention
      from its size or position; conspicuous; as, a prominent
      feature of the face; a prominent building.
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   3. Eminent; distinguished above others; as, a prominent
      character.
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   Prominent' moth (Zool.), any moth of the family
      Notodontid[ae]; a notodontian; -- so called because the
      larva has a hump or prominence on its back. Several of the
      species are injurious to fruit trees.
      [1913 Webster]