noun
Refers to a dull, persistent, or throbbing pain, often internal or emotional. Commonly used for toothaches, headaches, or heartache.
虫歯のうずきがひどくて眠れない。
The throbbing pain from my cavity is so bad I can't sleep.
失恋のうずきはなかなか消えない。
The ache of heartbreak doesn't go away easily.
痛み is the general word for physical or emotional pain, while うずき specifically suggests a throbbing, persistent ache.
疼く is the verb form meaning 'to ache' or 'to throb'; うずき is the corresponding noun.
Derived from the verb 疼く (うずく, 'to ache, throb'), of native Japanese origin. The kanji 疼 is a phono-semantic compound with 疒 (sickness) and 冬 (winter), suggesting a lingering, cold-like pain.