1. [n]  (Greek mythology) one of the heroes who sailed with Jason on the Argo in search of the Golden Fleece
2. [n]  someone engaged in a dangerous but potentially rewarding adventure

Argonaut
Mysterious bugs whose stings trigger an overload of memories are cropping up all over the place. Lester Ordway, medical tech Pilar Ramirez, and entomologist Maybelle Terwilliger suspect the bugs are the first signs of a pending alien invasion, and they must turn up credible evidence to prove this before it`s too late.

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1. \Ar"go*naut\, n. [L. Argonauta, Gr. ?; ? + ? sailor, ?
   ship. See {Argo}.]
   1. Any one of the legendary Greek heroes who sailed with
      Jason, in the Argo, in quest of the Golden Fleece.
   2. (Zo["o]l.) A cephalopod of the genus Argonauta.
   

2. \Ar"go*naut\, n.
   One of those who went to California in search of gold shortly
   after it was discovered there in 1848. [U. S.] --Bret Harte.
         The ``Argonauts of '49'' were a strong, self-reliant,
         generous body of men.                    --D. S.
                                                  Jordan.