Attenuated

This term is used to describe a vaccine that contains live but weakened viruses that will cause the body to develop an active immunity to them but will not normally cause disease.

From the BioTech Dictionary at http://biotech.icmb.utexas.edu/. For further information see the BioTech homenode.

At*ten"u*ate (#), At*ten"u*a`ted (#), a. [L. attenuatus, p. p.]

1.

Made thin or slender.

2.

Made thin or less viscid; rarefied.

Bacon.

© Webster 1913.