noun
iceberg lettuce
Refers specifically to the crisp, round-headed variety of lettuce. Common in supermarkets and recipes.
サラダに玉レタスをたっぷり入れました。
I put plenty of iceberg lettuce in the salad.
玉レタスは普通のレタスより日持ちがいい。
Iceberg lettuce keeps longer than regular lettuce.