Definition of "doubler" [dou•bler]

• A device that doubles the frequency or voltage of an input signal. (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.

• "Ye haue one sorte of repetition, which we call the doubler, and is as the next before, a speedie iteration of one word, but with some little intermission by inserting one or two words betweene, as in a most excellent dittie written by Sir Walter Raleigh these two closing verses:"
• "In the past, crews have repaired cracks in the external tank by removing the cracked aluminum and replacing it with a "doubler" -- a twice-as-thick section -- before replacing the foam insulation."
• "If you experience wetting problems, buy small "doubler" pads to add as needed."