What is the meaning of Overgrowth?

A usually abundant, luxuriant growth over or on something else. A tangle of growth occurring at the top of trees involving vines and branches, common in jungles.

An excessive growth or increase in numbers, as in a population of weeds or microbes.

Excessive size; usually caused by over-production of growth hormone from the pituitary gland.

Source: wiktionary.org