Correct spelling for the English word "Argumentable" is [ˈɑːɡjuːməntəbə͡l], [ˈɑːɡjuːməntəbəl], [ˈɑː_ɡ_j_uː_m_ə_n_t_ə_b_əl] (IPA phonetic alphabet).
That may be argued.
Etymological and pronouncing dictionary of the English language. By Stormonth, James, Phelp, P. H. Published 1874.