Like the Navajo language (5)
I believe the answer is:
tonal
'like the navajo language' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for tonal that I've seen before include "of sound quality" , "It's wood can be used to make twenty three dn" , "Like music that uses keys" , "of pitch" , "style of music" .)