Ǝ

Ǝ ǝ or Turned E is an additional letter of the Latin alphabet used in African languages using the Pan-Nigerian Alphabet or the African reference alphabet. The minuscule is based on a rotated e and the capital form majuscule Ǝ, based on a horizontally flipped majuscule E.

Not to be confused with U+2203 ∃ THERE EXISTS (HTML ∃ · ∃ · as a mathematical symbol).

In Windows, the uppercase "Ǝ" can be generated by holding the Alt key and pressing 398 on the number pad, and the lowercase "ǝ" with Alt + 477. In MacOS with the U.S. Extended keyboard, the letters Ǝ ǝ are made with Option-Shift-: followed by E e respectively.

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Wikipedia