乞

Originally related to 气 (air; breath; energy), 乞 and 气 were once the same character.

Over time:

气 retained meanings like “air” and “vital energy;” 乞 specialized into the meaning “to beg” or “to request.” This is an example of phonetic borrowing, where one character takes on multiple meanings and later splits into distinct forms.
Semantic development: - breath / air (original shared form with 气);

- asking or seeking;

- begging due to need;

- poverty and dependence.

Thus, 乞 evolved from a general concept of need to specific act of begging.

걸식 (乞食) — begging for food

구걸 (求乞) — begging

The separation of 乞 from 气 shows how Chinese characters evolve through semantic differentiation.

Compared to 求 or 請, 乞 carries a stronger emotional tone, often implying desperation or dependence. In modern usage, it is less common in everyday polite speech, appearing more in formal, literary, or historical contexts.
Related characters: 求 — to seek; to request

請 — to ask; to request (polite)

貧 — poverty

施 — to give (opposite perspective: giving vs begging)

Among these, 乞 emphasizes urgency and humility, often with social or economic hardship.