sledgehammer
A heavy hammer with a long handle, used for striking or driving stakes. The kanji 玄翁 is the most common spelling.
The carpenter is driving a stake with a sledgehammer.
金槌 is a standard claw hammer or metal hammer, typically smaller and used for driving nails, unlike the heavy 玄翁.
Standard kanji spelling for this word.
Ateji (phonetic) spelling; also encountered but less standard.
Kana spelling used when the kanji are not needed or for clarity.
Named for the legendary Zen monk 玄翁, who was said to have shattered the lethal 殺生石 with a large hammer; his name subsequently became a term for this kind of hammer.