Definition: A birth defect caused by a structural abnormality or a marked deviation from the average or norm; anything that is structurally unusual or irregular or contrary to a general rule a congenital defect. There are four clinically significant types of anomaly: malformation, disruption, deformation, and dysplasia.
[G. anōmalia, irregularity]
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Examples: glitazone, GI cocktail, etc.