trilateral
adjective uk/ˌtraɪˈlæt.ər.əl/ us/ˌtraɪˈlæt̬.ɚ.əl/
(GROUPS)
涉及三方的;涉及三国的
involving three groups or countries
A trilateral summit meeting was planned for the following month. 三方峰会计划在接下来的一个月举行。
(SIDES)
mathematics 有三边的
having three sides
trilateral shapes 三角形