iceberg lettuce

iceberg-lettuce的词性：
n.（名词）

1. A crisp, round, compact head of lettuce with light green, tightly folded leaves.
球叶莴苣：长有紧叠的淡绿色叶子的一种有脆而结实的圆头的莴苣

iceberg-lettuce的词源：

2. [From its pale color]
[源自其浅淡的颜色]