romaine (adj.)

type of lettuce, 1876, from French romaine (in laitue romaine, literally "Roman lettuce"), from fem. of Old French romain "Roman," from Latin Romanus (see Roman). Ayto ["Diner's Dictionary," 1990] defines it as "The American term for the long-leaved lettuce usually known to British-speakers as the cos lettuce," and writes that the name probably arose because it was imported into Western Europe from the eastern Mediterranean at first via the port of Rome. He compares Italian lattuga romana and notes that "the earliest English term for it, dating from the beginning of the seventeenth century, was Roman lettuce."

Definitions of romaine

romaine (n.)
lettuce with long dark-green leaves in a loosely packed elongated head;
Synonyms: cos / cos lettuce / romaine lettuce