Letters that make back-formation
a, o, b, f, k, n, c, m, r, t, i are letters that make 'back-formation'
Words within back-formation
OR, format, BA, MA, MAT, ti, FO, ma, Ba, AC, at, mA, mat, on, back, form, formation, Io, ion, Ac, At, Ti are words within 'back-formation'