trident
/ˈtraɪdənt/noun
1- a three-pronged spear, especially as an attribute of Poseidon (Neptune) or Britannia（尤指作为海神波塞冬或英帝国标志的）三叉戟。
1.1
Trident
a US design of submarine-launched long-range ballistic missile美国三叉戟潜射弹道导弹。
词源
late Middle English: from Latin trident-, from tri- 'three' + dens, dent- 'tooth'.