The province's name derives from the Zhe River (浙江, Zhè Jiāng), the former name of the Qiantang River which flows past Hangzhou and whose mouth forms Hangzhou Bay. It is usually glossed as meaning "Crooked" or "Bent River", from the meaning of Chinese 折, but is more likely a phono-semantic compound formed from adding 氵 (the "water" radical used for river names) to phonetic 折 (pinyin zhé but reconstructed Old Chinese *tet), preserving a proto-Wu name of the local Yue, similar to Yuhang, Kuaiji, and Jiang.
Is there an answer to this question (If it cannot be answered, say "unanswerable"): What does the mouth of the Qiantang River form?
Hangzhou Bay