watery grave

1. A place underwater where someone has drowned to death. Anyone who goes in the ocean with these intense rip currents is liable to end up in a watery grave. I need to get some rest before we get back on the road. The last thing I want is to fall asleep at the wheel and put us all in a watery grave.

2. A burial place in water for a dead body. The hitman tied cinderblocks to the informant's body and sent him to a watery grave. In olden times, sailors who died on the sea had to be thrown overboard into watery graves.