Sgian-dubh

The sgian-dubh (/ˌskiːən ˈduː/ skee-ən-DOO; Scottish Gaelic pronunciation: [s̪kʲɪnˈt̪uh]) is a small, single-edged knife (Gaelic sgian) worn as part of traditional Scottish Highland dress along with the kilt. Originally used for eating and preparing fruit, meat, and cutting bread and cheese – as well as serving for other more general day-to-day uses such as cutting material and protection, it is now worn as part of traditional Scottish dress tucked into the top of the kilt hose with only the upper portion of the hilt visible. The sgian-dubh is normally worn on the same side as the dominant hand.

The name comes from the Gaelic sgian-dubh. Although the primary meaning of dubh is "black", the secondary meaning of "hidden" is at the root of sgian-dubh, based on the stories and theories surrounding the knife's origin, in particular those associated with the Highland custom of depositing weapons at the entrance to a house prior to entering as a guest. Compare also other Gaelic word-formations such as dubh-sgeir "underwater skerry" (lit. black skerry), dubh-fhacal "riddle" (lit. hidden word), dubh-cheist "enigma" (lit. hidden question).

Despite this practice, a small twin edged-dagger, (a mattucashlass), concealed under the armpit, combined with a smaller knife, ('sgian-dubh'), concealed in the hose or boot, would offer an element of defence or of surprise if employed in attack.

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