well

1. Origins, structure, and basic meaning

• Structure: 井 is associated with a well and is written with four intersecting horizontal and vertical strokes.
• Basic usage: 井戸, read いど, refers to a well from which water is drawn.

2. Common pitfalls and similar expressions

• The word for a ceiling
  • 天井, read てんじょう, means the ceiling of a room.
  • The reading い for 井 in 井戸 does not carry over to 天井.
• Distinguishing 丼
  • 井 has no central dot, while 丼 does.
  • The well in 井戸 and 丼 in food names are not the same character.