강이나 하천의 상류 또는 발원지가 되는 물줄기.
The source or the upstream tributaries of a river or stream.
예문:
"The conservation project aims to protect the headwater from industrial pollution."
"Many rare species of trout are found only in the cold, clear headwaters of the mountain range."
"The river's headwater begins as a small spring deep within the forest."