water bug

Short definition from Wiktionary

Noun

1. 1
   Any member of the infraorder Nepomorpha, the true water bugs.
2. 2
   Any of various other true bugs that live around water.
3. 3
   An American cockroach of species Periplaneta americana.
4. 4
   An oriental cockroach of species Blatta orientalis.
5. 5
   Synonym of water strider.