chorionic villus sampling

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A prenatal test to detect birth defects that is performed at an early stage of pregnancy and involves retrieval and examination of tissue from the chorionic villi.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun medicine A form or prenatal diagnosis in which part of the placental tissue is tested for genetic abnormalities

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun a prenatal test to detect birth defects at an early stage of pregnancy; tissue from the chorionic villi is assayed