Meaning of headgate in English:
headgate
noun
1A gate for controlling the entry of water into a sluice, channel, etc.; specifically a gate or pair of gates at the upstream end of a canal lock.
2A gate at the end of a cage, pen, or chute, used as an aid to handling livestock, which allows the head to pass through but restrains the shoulders.
Origin
Late 18th century; earliest use found in John Smeaton (1724–1792), civil engineer.
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