Type of lettuce is a broad term that encompasses many different varieties. ICEBERG lettuce (7 letters) is a crunchy, light green lettuce with a mild flavor. Cos lettuce (3 letters) is a variety of ROMAINE lettuce with a slightly bitter taste and crisp texture. ROMAINE lettuce (7 letters) is a dark green lettuce with a crunchy texture and a slightly sweet flavor. Bibb lettuce (4 letters) is a buttery-textured lettuce with a mild flavor.