IPA: /ˈbækˌrʌʃ/
KK: /ˈbækˌrʌʃ/
The movement of water back to the sea after a wave has crashed onto the shore.
After the wave broke, the backrush pulled the sand back into the ocean.
Backrush is formed from "back" (from Old English "bæc", meaning the rear or behind) and "rush" (from Old English "rysce", meaning to move quickly or to hurry). The word describes a quick movement or return to a previous position or state, often in a sudden manner.
Think of moving quickly 'back' to a previous place or state — that's what 'backrush' means.