"tumblers" in the noun sense
a gymnast who performs rolls and somersaults and twists etc.
a glass with a flat bottom but no handle or stem originally had a round bottom
a movable obstruction in a lock that must be adjusted to a given position (as by a key) before the bolt can be thrown
4. roller, tumbler, tumbler pigeon
pigeon that executes backward somersaults in flight or on the ground
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