Vertically means that every class connected to the next class is connected to every class throughout the semester around a spiral.

纵向意味着每一节课都和下一节课有关系,和整个学期内的每一节课都有关系，呈一个螺旋状。

哈佛公开课 - 幸福课课程节选

What that means is that integrated vertically as well as horizontally.

就是指纵向的整体和横向的整体。

哈佛公开课 - 幸福课课程节选

I can also describe a particle going up and down.

我也可以描述一个质点的纵向运动

耶鲁公开课 - 基础物理课程节选

So it's vertically interconnected.

所以是纵向相互联系的。

哈佛公开课 - 幸福课课程节选

So here is a longitudinal study that was done by John Carter.

所以下面讲讲John，Carter所作的纵向研究。

哈佛公开课 - 幸福课课程节选