Definition of "upstroke" [up•stroke]

• An upward stroke, as of a brush. (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.

• "Their ghostly appearance is enhanced by the fact that the undersides of their chalk-white wings are dark brown, so with every upstroke they seem to disappear in the moonlight, then reappear on the downstroke."
• "With the upstroke everything advances to the next stage and a third case can be inserted in the holding plate."
• "Emerson, while you are singing lead, strum only the downstroke, leave out the upstroke, and see how that lets the chord ring."