Machete

A machete was a large knife used for fighting as well as for cutting food and plants.

Sontaran Field Major Styre used a machete to fight the Fourth Doctor. (TV: The Sontaran Experiment)

The Tenth Doctor and Rose Tyler used machetes to cut through foliage searching for the Dramos to cure Galathos of the sickwind. (COMIC: Blood and Tears)

Chris Cwej used one to cut open coconuts when he and the Seventh Doctor were stranded on an island. (PROSE: No Room)