The symbol is a letter of the Latin alphabet, used to represent a glottal stop in several phonetic transcription schemes, as well as in the alphabets of some languages. A superscript version, , is also used.Its shape is based on an enlarged curly apostrophe (ʼ), which is also widely used to represent a glottal stop.Where the glottal stop character is not available, it is sometimes replaced by a question mark (?), which is also its official representation in SAMPA, and to which it bears a striking resemblance.
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