Definition: Autosomal dominance is a pattern of inheritance characteristic of some genetic diseases. "Autosomal" means that the gene in question is located on one of the numbered, or non-sex, chromosomes. "Dominant" means that a single copy of the disease-associated mutation is enough to cause the disease. This is in contrast to a recessive disorder, where two copies of the mutation are needed to cause the disease. Huntington's disease is a common example of an autosomal dominant genetic disorder.
Source: National Human Genome Research Institute's Talking Glossary of Genetic Terms
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Autosomal Dominant
Source: National Human Genome Research Institute's Talking Glossary of Genetic Terms