godan verb (-ru), intransitive verb
complain of pain; show signs of pain
Describes someone visibly or audibly showing that they are in pain, often with a nuance of complaining or making a fuss. Formed from 痛い + がる (suffix for showing signs of a sensation).
子供が転んで痛がっている。
The child fell down and is complaining of pain.
He was showing signs of pain for a while after the injection.