纵深

纵深	zòng shēn	depth (from front to rear) / depth (into a territory) / span (of time) / (fig.) depth (of deployment, progress, development etc)
纵	zòng	vertical; north-south (Taiwan pr. [zong1]) / from front to back; longitudinal; lengthwise (Taiwan pr. [zong1]) / military unit corresponding to an army corps (Taiwan pr. [zong1]) / (bound form) to release (a captive) / to indulge / to leap up / (literary) even if
深	shēn	old variant of 深
深	shēn	(lit. and fig.) deep