EDIT Synonyms double pipe,

 siri  eki 

EDIT - Khoisan tradition - "x" in Zulu orthography

 siri  eki 

EDIT Linguistics In the international Phonetic Alphabet (IPA): alveolar lateral click. It is a sound that is found in some South African languages. The sound is created by quickly moving the side of the tongue away from the row of teeth, it is like the click that's used to hurry up a horse.

 eki  jsw 

EDIT International Phonetic Alphabet

+ Sound example

+ Alternatives // unknown
+ Former versions // ʖ (U+0296)

+ In the IPA since 1989
+ IPA number 180

+ This sound can be found in !Xóõ and Zulu.


Synonyms

English
+ Official name in the IPA // ›alveolar lateral click‹
+ Nonstandard // similar to clicking of the tongue
+ Double Pipe


+ Source //
Principles of the International Phonetic Association, London, 1949. /
Journal of the International Phonetic Association, 1989. /
Wikipedia. Die Liste der IPA-Zeichen & History of the International Phonetic Alphabet. /
Handbook of the International Phonetic Association: A Guide to the Use of the International Phonetic Alphabet. /
Pullum, Geoffrey and William A. Ladusaw. Phonetic Symbol Guide. Second edition.

 FrauFriedrich