This is the 4897th most frequent Japanese word.
甲羅
Shell (of a turtle or crustacean).
In this sentence, '甲羅' (shell) refers to the protective covering of the turtle.
カメは甲羅を持っています。
The turtle has a shell.
Here, '甲羅' (shell) is used metaphorically to describe a hidden or protective barrier.
彼の言葉はまるで甲羅に隠れたもののようだ。
His words are like something hidden in a shell.
In this sentence, '甲羅' (shell) is employed in a simile to describe the toughness or hardness of the skin.