Definition of "fill-in" []

• Informal One that serves as a substitute for another. (noun)
• Informal A short informative summary. (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.

• ""We lost some of what we call the fill-in trip," Chief Financial Officer Charles Holley said."
• "Depending on how Marve's knee fares this summer, TerBush would serve as a capable fill-in."
• "DT Hollis Thomas was a quality one-year fill-in who helped solidify a nose tackle position devastated by injuries."