This is the 2773rd most frequent Japanese word.
貝
"Shell" or "shellfish."
The word 貝 is used to refer to seashells, highlighting their natural beauty.
私は海で美しい貝をたくさん見つけました。
I found many beautiful shells at the beach.
Here, 貝殻 refers to the shells themselves as collectible objects.
貝殻を集めるのが弟の趣味です。
Collecting shells is my younger brother's hobby.
In this sentence, 貝 indicates edible shellfish, emphasizing its use as food.