Portuguese military adventurer who sailed with João Gonçalves Zarco in the Atlantic Ocean, where off the northwest coast of Africa they discovered an unclaimed island with fresh water and fertile soil, which they named Porto Santo, meaning "holy haven." Around 1420 Teixeira returned with Zarco to the island to form a colony, whose first governor, Bartolomeu Perestrello, later became the father-in-law of Christopher Columbus. Though unsuccessful, the colony was a starting point for further Portuguese explorations commissioned by Prince Henry the Navigator and would lead to the discovery of Madeira, sighted nearby.