flash-board

The farmer uses a flash-board to control the water flow in the irrigation ditch.

Definition

Noun: A "flash-board" is a board or plank placed on top of a dam or weir to raise the water level temporarily, allowing for controlled overflow when the water rises above it.

Usage Examples

• (A board that can be removed to allow excess water to pass.)
• (The board acted as a temporary barrier that yields under pressure.)

Advanced Usage

• "to adjust the flash-board": to modify the height of a dam by adding or removing boards.

  • Farmers adjust the flash-board to maintain irrigation levels in the canal. (They change the board's position to control water volume.)

• "flash-board weir": a type of weir equipped with movable boards for regulating water flow.

  • The flash-board weir is common in small-scale hydroelectric projects. (A weir designed with removable planks.)

Variants and Related Words

• Flashboard (n): alternative spelling, often used interchangeably.

  • The flashboard was made of treated wood to resist rot. (The same structure as flash-board.)

• Flashboard dam (n): a dam that uses flash-boards to increase storage capacity.

  • The flashboard dam allows seasonal water management. (A dam with adjustable boards.)

Synonyms

• Stop-log: a log or plank used similarly to regulate water flow in a dam.
• Crest gate: a movable gate on a dam's crest for overflow control.

Related Idioms

• "to be on the flash-board": (rare) to be in a temporary or precarious situation.
  • His job was on the flash-board, dependent on seasonal rains. (His position was unstable and subject to change.)

Phrasal Verbs

• Flash out: to remove a flash-board to release water.
  • They had to flash out the boards after the storm. (They took the boards away to let water flow freely.)