One who clows; a person who operates a sluice gate or controls water flow in drainage and dike systems.
From clow + -er (a suffix meaning 'one who does'). Occupational term created to describe the person responsible for managing water flow in Dutch and English waterworks.
Every specialized job created specialized words—a 'clower' was as important to Dutch society as a plumber is today, because mismanaging water meant floods and disaster.
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