15-letter words containing o, a, f, i, s
- usman dan fodio — 1754–1817, African mystic and revolutionary leader, who created a Muslim state in Nigeria
- vicar of christ — the pope, with reference to his claim to stand in the place of Jesus Christ and possess His authority in the church.
- witch of agnesi — a plane curve symmetrical about the y- axis and asymptotic to the x- axis, given by the equation x 2 y =4 a 2 (2 a − y).
- yeast infection — candida: genital inflammation
- yellow goatfish — a schooling goatfish, Mulloidichthys martinicus, inhabiting the Atlantic Ocean from Florida to Panama.