upstroke

American  

[uhp-strohk] / ˈʌpˌstroʊk /

noun

1. an upward stroke, especially of a pen or pencil, or of a piston in a vertical cylinder.

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upstroke British  

/ ˈʌpˌstrəʊk /

noun

1. 1. an upward stroke or movement, as of a pen or brush

   2. the mark produced by such a stroke

2. the upward movement of a piston in a reciprocating engine

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Etymology

Origin of upstroke

First recorded in 1820–30; up- + stroke ¹

Example Sentences

See Examples For:

upstroke

In our hippogriff, the muscles of the back drive the upstroke, and the muscles of the chest power the downstroke, just as in living bats and long-extinct pterosaurs.

From Scientific American ● Apr. 9, 2021

A hydrodynamic analysis of the humpback's movements in the lab confirmed that both the upstroke and the downstroke of its flippers provide forward thrust.

From National Geographic ● Jul. 12, 2017

The heart relaxes and refills on the upstroke.

From Time Magazine Archive

The major part of the current flow is the high, thin upstroke of the "R" wave; the thin downstroke is simply return to the base line.

From Time Magazine Archive

It is particularly noticeable in the writing of those who have been instructed in the old-fashioned school, where a distinction between the heavy downstroke and the light upstroke was insisted upon.

From The Detection of Forgery A Practical Handbook for the Use of Bankers, Solicitors, Magistrates' Clerks, and All Handling Suspected Documents by Blackburn, Douglas