[1] : The Collaborative International Dictionary of English v.0.48

forerunner \forerun"ner\, n.
   1. a messenger sent before to give notice of the approach of
      others; a harbinger; a sign foreshowing something; a
      prognostic; as, the forerunner of a fever.
      1913 webster

            whither the forerunner in for us entered, even
            jesus.                                --heb. vi. 20.
      1913 webster

            my elder brothers, my forerunners, came. --dryden.
      1913 webster

   2. a predecessor; an ancestor. obs. --shak.
      1913 webster

   3. naut. a piece of rag terminating the log line.
      1913 webster

[2] : WordNet (r) 2.0

forerunner
     n 1: anything that precedes something similar in time;
          "phrenology was an antecedent of modern neuroscience"
          syn: antecedent
     2: a person who goes before or announces the coming of another
        syn: precursor
     3: an indication of the approach of something or someone syn:
        harbinger, herald, precursor
see also:
antecedent precursor harbinger herald 

[3] : Moby Thesaurus II by Grady Ward, 1.0

101 moby thesaurus words for "forerunner":
   gabriel, mahdi, advertisement, advertiser, ancestor, announcement,
   announcer, antecedent, augury, author, avant-garde, bell cow,
   bell mare, bellwether, born leader, buccinator,
   buccinator novi temporis, bushwhacker, charismatic leader,
   choirmaster, choragus, coach, conductor, coryphaeus, duce, envoy,
   evangel, evangelist, example, exemplar, explorer, file leader,
   forebear, forefather, foregoer, foreshadow, foreshadower,
   foretoken, forewarning, front runner, frontiersman, fugleman,
   groundbreaker, guide, harbinger, herald, herald angel, initiator,
   innovator, inspired leader, instructor, lead runner, leader,
   leader of men, mark, mentor, messenger, messiah, model, omen,
   originator, outrider, pacemaker, pacesetter, pathfinder, pattern,
   pioneer, point, portent, precedent, precentor, precursor,
   predecessor, premise, premonition, premonitor, preparationist,
   preparator, preparer, presage, presager, progenitor, prognostic,
   prototype, ringleader, scout, sign, standard-bearer, stormy petrel,
   symphonic conductor, symptom, teacher, token, torchbearer,
   trailblazer, trailbreaker, trainer, vanguard, vaunt-courier,
   voortrekker, warning

[4] : Easton's 1897 Bible Dictionary

forerunner
   john the baptist went before our lord in this character mark
   1:2, 3. christ so called heb. 6:20 as entering before his
   people into the holy place as their head and guide.
   

Forerunner >> F Words
Forerunner, definition of term: Forerunner
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