One who on the basis of religious or moral principles refuses to bear arms or participate in military service.(noun)
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.
Use "conscientious objector" in a sentence
"The reason that San Antonio was so important as a conscientious objector center was that this was where the 1-A-O conscientious objectors were sent."
"ODonnell responded that this would be a disaster, because Sorensen had been a conscientious objector to military service and could not therefore argue credibly for the use of force."