In a lexical tone language, a tone which is not initially associated with a syllable, but which attaches itself to a neighbouring syllable or causes downstep or upstep of a neighbouring tone. An example from Bambara (Mali): the definite article is a floating low tone. This attaches itself to a preceding noun, and if this has a high tone, this is turned into a falling (HL) tone. ba with high tone means “river”, but with a falling tone it means “the river”.
H L H L
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ba (def.) ba