Tumbler (noun)

1. A gymnast who performs rolls, somersaults, and other acrobatic feats.
2. A container, typically made of glass or plastic, with a flat base and straight sides, used for drinking.
3. A lock or latch with a mechanism that can be moved only by rotating a cylinder or by manipulating a series of pins.

Origin:

Middle english: from old french tumbler, from tumbler "to tumble", of imitative origin.

Examples:

1. The young tumbler performed a series of impressive flips and twists.
2. He poured water into a tumbler and took a sip.
3. The tumbler lock required a specific sequence of numbers to open.
4. The whiskey tumbler is a popular choice for drinking spirits neat.
5. The tumbler on the safe was broken and it wouldn't open.