餌

1. Origins, structure, and basic meaning

• Structure: 餌, read えさ, is a noun meaning animal feed or bait.
• Basic usage: The same material may be described as feed or bait depending on whether it nourishes or attracts an animal.

2. Common pitfalls and similar expressions

• The animal receiving food
  • 魚に餌を与える means giving food to fish.
  • に marks the fish receiving the food, and を marks the food being given.
• Where bait is attached
  • In 釣り針に餌を付けて, the hook is where the bait is attached. Here, に marks an attachment point, not an animal receiving food.