'Tumbler' definitions:

Definition of 'tumbler'

noun

A gymnast who performs rolls and somersaults and twists etc.

noun

A glass with a flat bottom but no handle or stem; originally had a round bottom

noun

A movable obstruction in a lock that must be adjusted to a given position (as by a key) before the bolt can be thrown

noun

Pigeon that executes backward somersaults in flight or on the ground [syn: roller, tumbler, tumbler pigeon]

From: GCIDE

Tumbler \Tum"bler\, n.
1. One who tumbles; one who plays tricks by various motions of the body; an acrobat. [1913 Webster]
2. A movable obstruction in a lock, consisting of a lever, latch, wheel, slide, or the like, which must be adjusted to a particular position by a key or other means before the bolt can be thrown in locking or unlocking. [1913 Webster]
3. (Firearms) A piece attached to, or forming part of, the hammer of a gunlock, upon which the mainspring acts and in which are the notches for the sear point to enter. [1913 Webster]
4. A drinking glass, without a foot or stem; -- so called because originally it had a pointed or convex base, and could not be set down with any liquor in it, thus compelling the drinker to finish his measure. [1913 Webster]
5. (Zool.) A variety of the domestic pigeon remarkable for its habit of tumbling, or turning somersaults, during its flight. [1913 Webster]
6. (Zool.) A breed of dogs that tumble when pursuing game. They were formerly used in hunting rabbits. [1913 Webster]
7. A kind of cart; a tumbrel. [Prov. Eng. & Scot.] [1913 Webster]