Two people or two groups resembling each other so closely that they are practically indistinguishable.
Two persons or things so much alike as to be almost indistinguishable.
Two droll, almost identical brothers in Through the Looking-Glass, by Lewis Carroll.
(pejorative, idiomatic) Two persons or organizations deemed indistinguishable in some way.
The radicals said that Nixon and Humphrey were Tweedledum and Tweedledee.
(pejorative, idiomatic) A pair of people who spend a lot of time together, and look and act similarly.
Origin of tweedledum-and-tweedledee
- After Tweedledum and Tweedledee , names of two proverbial rival fiddlers, of imitative origin
From American Heritage Dictionary of the English Language, 5th Edition
- From Tweedledum and Tweedledee, a pair of identical characters in Lewis Carroll's Through the Looking-Glass, and What Alice Found There