tumbler vs tumbler pigeon

tumbler and tumbler pigeon both are nouns.

Word	Noun	Adjective	Verb	Adverb
tumbler	Yes	No	No	No
tumbler pigeon	Yes	No	No	No

As nouns, tumbler and tumbler pigeon are synonyms defined as:

tumbler and tumbler pigeon: pigeon that executes backward somersaults in flight or on the ground

Other synonyms of tumbler include roller.

tumbler (noun)	tumbler pigeon (noun)
pigeon that executes backward somersaults in flight or on the ground	pigeon that executes backward somersaults in flight or on the ground
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
a gymnast who performs rolls and somersaults and twists etc.