A caltrop is common name given to some (unrelated) plants that have seed heads with 4 or more sharp spikes, arranged so that one of them is always pointing upwards. The seed heads are very painful to step on.
Metal devices of the same name and design can be thrown onto roads in front of cars to burst their tires.
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Fis forFlip flops
A gallop is the fastest gait of a horse. It has a beat of four, and all of the horse's feet are off the ground at once as it is galloping.
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Scientific name: humulus lupulus
Hops is a plant grown for its flowers, which are added to beer to make it bitter. The hop plant is a climbing plant that is usually grown up poles or on strings in a field. Hop plants can grow very fast, and climb by wrapping themselves clockwise around anything they bump into. It grows vigorously in spring but dies back to a frost-hardy bulb in autumn.