Meaning and Usage
The character 凹 (āo) primarily describes a surface that is concave or hollowed inward. It is often used to describe physical shapes such as dents, pits, or hollows on objects or surfaces.
Common Collocations
- 凹陷 (āoxiàn): dent or depression, often used for damage or natural hollows.
- 凹坑 (āokēng): pothole or pit, commonly used for roads or ground.
Usage Notes
凹 is mostly used as an adjective or part of compound nouns describing shapes. It contrasts with 凸 (tū), which means convex or protruding. When describing objects, 凹 emphasizes an inward curve or depression.
Register and Tone
凹 is neutral in tone and can be used in both formal and informal contexts. It is more common in written descriptions, technical language, or when specifying shapes.
Common Confusion
Do not confuse 凹 with 凸. 凹 means concave (inward), while 凸 means convex (outward). Using one instead of the other changes the meaning completely.