What does "roach" mean?

Roach: (Zoöl.) (a) A European fresh-water fish of the Carp family (Leuciscus rutilus). It is silver-white, with a greenish back. (b) An American chub (Semotilus bullaris); the fallfish. (c) The redfin, or shiner.

Additional senses

  1. 2.(Naut.) A convex curve or arch cut in the edge of a sail to prevent chafing, or to secure a better fit. As sound as a roach Etym: [roach perhaps being a corruption of a F. roche a rock], perfectly sound.
  2. 3.To cause to arch.
  3. 4.To cut off, as a horse's mane, so that the part left shall stand upright.

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