Definition of "aerobics" []

• A system of physical conditioning designed to enhance circulatory and respiratory efficiency that involves vigorous sustained exercise, such as jogging, swimming, or cycling. (noun)
• A program of physical fitness that involves such exercise. (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.

• "‡ The term aerobics usually refers to a specific kind of vigorous exercise, sometimes involving dance steps, that is set to music."
• "The word 'aerobics' came about when the gym instructors got together and said: If we're going to charge $10 an hour, we can't call it 'Jumping up and down.'"
• "My knee is feeling better so I think I'll do 20 min aerobics, 20 min toning."