| Noun | 1. | overgrowth - excessive size; usually caused by excessive secretion of growth hormone from the pituitary gland hyperpituitarism - excessive activity of the pituitary gland (especially overactivity of the anterior lobe which leads to excess secretion of growth hormone) hypertrophy - abnormal enlargement of a body part or organ |
| 2. | overgrowth - a profusion of growth on or over something else profuseness, profusion, richness, cornucopia - the property of being extremely abundant; "the profusion of detail"; "the idiomatic richness of English" |