Definition of "acellular" []

• Containing no cells; not made of cells. (adjective)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "Because of the high rate of side effects, scientists developed a more purified version of the pertussis vaccine, referred to as the acellular pertussis vaccine."
• "A newer version of the vaccine, called the acellular pertussis vaccine, contains fewer pertussis proteins and causes fewer reactions."
• "He was an early champion for the introduction of safer whooping cough vaccines, called acellular vaccines."