What is the X in X-mas?
1520s, from Middle French caravelle (15c.), from Spanish carabela or Portuguese caravela, diminutive of caravo "small vessel," from Late Latin carabus "small wicker boat covered with leather," from Greek karabos, literally "beetle, lobster" (see scarab). Earlier form carvel (early 15c.) survives in carvel-built (adj.).
a light sailing ship of the 15th, 16th, and 17th centuries in Europe, much-used by the Spanish and Portuguese for long voyages. Apparently developed by the Portuguese for exploring the coast of Africa, the caravel's chief excellence lay in its capacity for sailing to windward. It was also capable of remarkable speed. Two of the three ships in which Christopher Columbus made his historic voyage in 1492 were caravels, the Nina and the Pinta.