Maternal rhymes with:
fraternal, paternal, eternal, external, fraternal, internal, nocturnal, paternal, bernal, burnell, colonel, diurnal, durnell, durnil, eternal, external, fraternal, infernal, internal, journal, kernel, nocturnal, paternal, pernell, purnell, vernal
Maternal sounds like:
matrimonial, matronly, metromail, mother-in-law