Definition of "water-bug" [water-bug]

• Any true bug of the heteropterous section Hydrocorisæ or Cryptocerata, including those which live beneath the surface of the water. and belong to the families Corisidæ, Notonectidæ, Nepidæ, Belostomidæ, and Naucoridæ. See these words, and cuts under Belostoma and Ranatra. (noun)
• Any one of certain true bugs of the heteropterous section Aurocorisa, including those which live mainly on the surface of the water, and which belong to the families Hydrobatidæ, Veliidæ, Limnobatidæ, Saldidæ, and Hydrometridæ. See these words. (noun)
• The croton-bug or German cockroach, Blatta (Phyllodromia) germanica: so called from its preference for water-pipes and moist places in houses. See cuts under croton-bug and Blattidæ (noun)

The Century Dictionary (Public Domain)

• "In your lunch bag put a large dead water-bug cockroach in a clear plastic bag on top of the container which holds your sandwich."
• "You can even detect a water-bug (Gyrinus) ceaselessly progressing over the smooth surface a quarter of a mile off; for they furrow the water slightly, making a conspicuous ripple bounded by two diverging lines, but the skaters glide over it without rippling it perceptibly."
• "There's one, for instance, where I emerge into a sepia-toned Manhattan, its skyscrapers covered by the chitinous shells of massive insects with water-bug antennae waving menacingly from their roofs."