General "thin":
* 薄い (usui): This is the most common word for thin, used for a variety of situations.
* Example: 薄い本 (usui hon): a thin book
Specific types of "thin":
* 細い (hosoi): This refers to thinness in a linear sense, like the thickness of a wire or a person's waist.
* Example: 細い糸 (hosoi ito): a thin thread
* 軽い (karui): This means "light," but can also be used to describe something that is thin and easy to move.
* Example: 軽い布 (karui nuno): a light (thin) cloth
* 薄い (usui): Can also be used for thinness in terms of color or density.
* Example: 薄い色 (usui iro): a pale color
* 弱々しい (yowayowashii): This is more metaphorical, and describes something that is "fragile" or "weak" because it is thin.
* Example: 弱々しい紙 (yowayowashii kami): thin and flimsy paper
The best word to use will depend on the specific context and the nuance you want to convey.