AlamoyoudaoicibaDictYouDict[Alamo 词源字典]
nickname of Franciscan Mission San Antonio de Valeroin (begun 1718, dissolved 1793) in San Antonio, Texas; American Spanish, literally "poplar" (in New Spain, also "cottonwood"), from alno "the black poplar," from Latin alnus "alder" (see alder).

Perhaps so called in reference to trees growing nearby (compare Alamogordo, New Mexico, literally "big poplar," and Spanish alameda "a public walk with a row of trees on each side"); but the popular name seems to date from the period 1803-13, when the old mission was the base for a Spanish cavalry company from the Mexican town of Alamo de Parras in Nueva Vizcaya.[Alamo etymology, Alamo origin, 英语词源]