[kaon_]

Super-interesting side-tangent:

There is a theory that the clicking sounds present in many African languages originate from taboos like these. Basically they would use a click as "you-know-who".

Source: I heard it on TheGreatCourses at some point.

[bradrn]

It’s more complicated than that. The taboo in this case is hlonipha [0] amongst Bantu peoples, in which you cannot say the name of certain relatives, or any word which sounds like their name. By this stage, clicks had already entered Bantu languages from Khoisan ones [1], and had already started to spread through the native vocabulary. Hlonipha simply sped up that process — if you want to say a word you’re not allowed to say, it’s easy to just substitute a sound with a click.

[0] https://en.wikipedia.org/wiki/Avoidance_speech#Africa

[1] https://en.wikipedia.org/wiki/Khoisan_languages

[defrost]

That doesn't exactly mesh with the way that !Xhosa speakers talk about their language, eg:

https://www.youtube.com/watch?v=baEiWB2aM9Y

https://youtu.be/KZlp-croVYw?t=16

https://en.wikipedia.org/wiki/Xhosa_language