An iron rod used for beating down the earthy substance in tamping for blasting.

plural of tamping iron

simple past tense and past participle of tamp down

present participle of tamp down

To compact a substance (usually soil) until it is flat. / (idiomatic, by extension) To suppress (something, usually an emotion or thought).

plural of tamping machine

(rail transport) A self-propelled rail-mounted machine used to pack or tamp ballast under railway tracks; a ballast tamper.