na-adjective, noun
Describes actions or methods that are physically rough, forceful, or lacking gentleness. Often used for handling things or treating people.
彼は手荒な扱いで箱を壊してしまった。
He broke the box with rough handling.
警察の手荒な捜査が問題になった。
The police's heavy-handed investigation became an issue.
Compound of 手 (hand, method) and 荒 (rough, violent). The exact historical derivation is uncertain, but the meaning is transparent from its components.