hypertrophy

n. abnormal enlargement of a part or organ; excessive growth

v. affect with hypertrophy; be affected with hypertrophy

Hypertrophy is the increase of the size of an organ or in a select area of the tissue. It should be distinguished from hyperplasia which occurs due to cell division increasing the number of cells while their size stays the same; hypertrophy occurs due to an increase in the size of cells, while the number stays the same.
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Hypertrophy /hy·per·tro·phy/ enlargement or overgrowth of an organ or part due to increase in size of its constituent cells. [more]Hypertrophy - Community and Resources

Noun
1. abnormal enlargement of a body part or organ
(hypernym) dysplasia
(hyponym) adenomegaly
Verb
1. undergo hypertrophy; "muscles can hypertrophy when people take steroids"
(hypernym) grow

(n.)
A condition of overgrowth or excessive development of an organ or part; -- the opposite of atrophy.