trilithon
/traɪˈlɪθɒn/(亦作trilith /ˈtraɪlɪθ/)
noun
- Archaeology a megalithic structure consisting of two upright stones and a third across the top as a lintel【考古】巨石牌坊（两巨石作柱, 上架一巨石作梁）。
词源
mid 18th cent.: from Greek, from tri- 'three' + lithos 'stone'.