semi-major axis

semimajor axis of ellipsoid椭球长半轴，地球长半轴xDk汉语字典

Either half of the major axis is called a semimajor axis.长轴的每一半叫做半长轴。xDk汉语字典

one-half the major axis of an ellipse; the distance from the center of an ellipse to one end.椭圆长轴的一半；从椭圆的中心到一端的距离。xDk汉语字典

The major semiaxis a and p of the relative orbital motion are known.我们知道其相对轨道运动的主要半长轴a和周期p。xDk汉语字典

Relationships between the minor axis semidiameter and major axis semidiameter have been empirically determined for different structural detail geometries.对于不同结构细节的几何形状，已经确定了短轴和长轴半径之间的关系。xDk汉语字典

leading half axle（拖拉机转弯时）前进半轴xDk汉语字典

multi-spindle vertical semi-automatic lathe立式多轴半自动车床xDk汉语字典

crankcase bottom half发动机曲轴箱的下半部xDk汉语字典

reentrant cylindrical cavity圆柱形凹腔, 半同轴空腔xDk汉语字典

rear axle differential side gear后桥差速器半轴齿轮xDk汉语字典

The camshaft rotates in phase with the crankshaft, but at half its speed.凸轮轴和曲轴协调旋转, 但速度仅是曲轴的一半。xDk汉语字典

A vertical Japanese scroll painting.字轴，画轴，长轴一种垂直（悬挂）的日本卷轴画xDk汉语字典

To create torque in a long axis stroke( freestyle and backstroke), one must have a semi-fixed point from which to work.为了在长轴划水（由泳和仰泳）建立扭矩，一个人必须在运动中有一个半稳定点。xDk汉语字典

Five paces by four and a half.'五步长四步半宽。”xDk汉语字典

A short shaft that transmits motion from a motor to a machine, especially in an automobile.传动轴，驱动半轴从马达传送动作给机器的短轴，尤指汽车xDk汉语字典

High quality bearing steel is selected to prolong the beering's service life.轴承选用精制轴承钢，使用寿命长。xDk汉语字典

Cytyledons and future stalk called the hypocotyl elongate.子叶和未来称为下胚轴的主轴延长。xDk汉语字典

Application of Oil-free Lubricating Material to Long Shaft Bearings for Dog Transfer拨入机长轴轴承无油润滑材料的应用xDk汉语字典