[420] Formāl (Chem.), so v.w. Formyloxydhydrat-Methyloxyd, s.u. Formyl.
Brockhaus-1911: Formal
Eisler-1904: Formal
Herder-1854: Formal
Kirchner-Michaelis-1907: formal
Meyers-1905: Formāl
Pierer-1857: Formāl [1]