Correct spelling for the English word "tannal" is [tˈanə͡l], [tˈanəl], [t_ˈa_n_əl] (IPA phonetic alphabet).
A brownish yellow powder employed locally as an astringent; soluble t. is aluminum tannotartrate; insoluble t., aluminum tannate.
A practical medical dictionary. By Stedman, Thomas Lathrop. Published 1920.