noun Riv·u·lus \-ləs\

Definition of Rivulus

  1. :  a large genus of brightly colored but often sluggish South and Central American killifishes several species of which are sometimes kept in a tropical aquarium

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Origin and Etymology of rivulus

New Latin, from Latin, rivulet — more at rivulet

Seen and Heard

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feeling or affected by lethargy

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