from The American Heritage® Dictionary of the English Language, 4th Edition
- n. Incomplete or arrested development of an organ or a part.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. underdevelopment or incomplete development of a tissue or organ, especially when caused by an inadequate or below-normal number of cells
from The Century Dictionary and Cyclopedia
- n. Deficient growth or atrophy of a part through excessive destruction or defective formation of cells.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. underdevelopment of an organ because of a decrease in the number of cells
hypo- + -plasia (Wiktionary)