noun Etymology: English tweedle to chirp + dum (imitative of a low musical note) & dee (imitative of a high musical note) Date: 1725 two individuals or groups that are practically indistinguishable
TWEEDLEDUM AND TWEEDLEDEE
Meaning of TWEEDLEDUM AND TWEEDLEDEE in English
Merriam Webster. Explanatory English dictionary Merriam Webster. Толковый словарь английского языка Мерриам-Уэбстер. 2012