The word 'trident' is a direct borrowing from the Latin tridēns, trident-, which is a compound of tri- (three) and dēns (tooth). This literal construction, meaning "three-toothed," perfectly describes the physical object: a spear or fork with three sharp prongs. In classical mythology, the trident was the distinctive attribute of the sea god Neptune (Greek Poseidon), symbolizing his power over the oceans. Over time, the term has been extended metaphorically to denote any three-pronged instrument or symbol, and in modern military contexts, it lends its name to weapon systems like the submarine-launched ballistic missile, evoking an image of formidable, multi-pronged force.

Structure: tri (three) + dent (tooth) - tri: From Latin tri-, from Greek tri-, from Proto-Indo-European tréyes (three). A numerical prefix. - dent: From Latin dent-, stem of dens (tooth). A root denoting a tooth or pointed projection.