鳥

It is a pictograph created to resemble the shape of a bird.

According to the Shuowen Jiezi (an ancient Chinese dictionary), it represents birds with long tails, in contrast to 隹 (chui), which denotes birds with short tails. However, based on the entry for 隹, this explanation seems to be incorrect. In oracle bone script, 隹 was generally used to represent “bird.”

The form of 鳥 varies greatly in ancient characters, which suggests that the 鳥 character in oracle script may have represented specific bird species, rather than birds in general. As a result, many more ancient characters were based on 隹 than on 鳥. The characters using 鳥 were created comparatively later. It is likely that as 隹 began being used for other meanings (through phonetic borrowing), 鳥 started to be used more specifically to mean "bird" in order to avoid confusion.

As a radical, 鳥 can appear in various positions (left, side, or bottom).

True to its meaning, it appears as a component in many characters related to birds and avian species, such as:

鷄 (chicken)

鳩 (pigeon)

鳯 (phoenix)

䲨 (wild goose)

鴨 (duck)

Historically, the Middle Chinese pronunciation of 鳥 was/teu/, with the fanqie spelling 都了切. However, because this pronunciation was identical to 屌 (diǎo, meaning "penis"), it gained an undesirable connotation. To avoid this, the modern pronunciation "niǎo" (a borrowed reading) replaced it as the standard.

Some even speculate that 鳥 itself might be the etymological origin of 屌, due to the resemblance between a bird’s head or baby bird and male genitalia. While only the pronunciation changed and not the character, 鳥 is still used as a vulgar term in Chinese, particularly in colloquial contexts.

It is easily confused with the character 烏 (crow, 오), which looks very similar—the "日" part in 鳥 becomes "口" in 烏. Since the difference is only one stroke, on low-resolution screens, like 10pt font it may appear as just a 1-pixel difference, making them hard to distinguish.

Also, be cautious not to confuse it with 島 (island 도), which also contains 鳥 as a component.