四维的，四度空间的由四维确定或表现的，尤指三个空间维度和相对理论中的时间维度 Specified by or exhibiting four dimensions, especially the three spatial dimensions and single temporal dimension of the relativity theory.
信息密度在一个线性维度内有用的信息单元的个数 The number of units of useful information contained within a linear dimension.
