二股流：secondary air (flow) (of turbine engine combustor)
二鼓法：two-drum system
二管轮：second asistant engineer,second engineer,third engineer
二化性：bivoltine
二环的：bicyclic
二环烃：bicyclic hydrocarbon
二磺酸：disulfonic acid
二级半：Fully good Fair to Good;Fully Good to Fine
二级波：wave of the second order
二级风：light breeze
二级栈：second-level stack
二级站：secondary station
二极的：ambipolar
二甲碲：methyl-telluride
二甲汞：dimethyl mercury
二甲精：glycerin diformate,diformin
二甲灵：dimethyline
二甲镁：magnesium methide
二甲铍：beryllium methide,beryllium methyl
二甲桥：dimethano
二甲砷：arsenic dimethyl
二甲胂：cacodyl hydride,dimethyl arsine
二甲蹄：dimethyl telluride
二甲硒：dimethyl selenide
二甲锡：methyl-tin
二甲锌：dimethyl zinc,zinc dimethyl
二甲酯：dimethyl ester
二价醇：divalent alcohol
二价的：bivalent,divalent,dyad
二价碱：diatomic base
二价酸：diatomic acid
二芥精：dierucin
二肼羰：carbazide,carbohydrazide
二聚的：dimeric
二聚水：dihydrol
二糠酰：difurfuroyl
二孔型：bifora
二苦硫：dipicryl sulfide
二蜡精：dicerotin
二联脉：bigeminy,bigeminal pulse
二裂的：bifid
二磷酸：diphosphate
二磷烷：diphosphane,diphosphine
二龄鲑：smolt
二硫胺：thiamine disulfide
二硫酚：dithiol
二硫酮：dithione
二卤的：dihalo
二路栓：two-way tap,two-way cock
二氯芬：dichlorophen