Ĝ or ĝ (G circumflex) is a consonant in Esperanto orthography, representing a voiced postalveolar affricate (either palato-alveolar or retroflex), and is equivalent to a voiced postalveolar affricate /dʒ/ or a voiced retroflex affricate /dʐ/.
While Esperanto orthography uses a diacritic for its four postalveolar consonants, as do the Latin-based Slavic alphabets, the base letters are Romano-Germanic. Ĝ is based on the letter g, which has this sound in English and Italian before the vowels i and e (with some exceptions in English), to better preserve the shape of borrowings from those languages (such as ĝenerala from general) than Slavic đ would.
Ĝ is the ninth letter of the Esperanto alphabet. Although it is written as gx and gh respectively in the x-system and h-system workarounds, it is normally written as G with a circumflex: ĝ.
Uses of Ĝ in other languages
In Haida, a language isolate, the letter ĝ was sometimes used to represent pharyngeal voiced fricative /ʕ/
In Aleut, an Eskimo-Aleut language, ĝ represents a voiced uvular fricative /ʁ/. The corresponding voiceless Aleut sound is represented by x̂.
In Dutch, the letter ĝ is used in some phrase books and dictionaries for pronunciation help. It represents a plosive [ɡ], because g is pronounced as a fricative /ɣ/ in Dutch.
In some transcriptions of Sumerian, ĝ is used to represent the velar nasal /ŋ/.