In the
field of
linguistics, the particular
alphabet used is the
International Phonetic Alphabet or
IPA, which has a
symbol for each and every
distinct sound that a
human is capable of
vocalizing, including "clicks" and other such
glottal stops.
The use of "niner" in
aviation and
aerospace came about because "nein" (pronounced like the
English "nine"), in
German, means "no". There was the
potential for a lot of
confusion without the use of
niner.