"To wake the screen" means to turn on or activate the display of an electronic device such as a smartphone, computer, or TV that was previously turned off or in standby mode. Full definition
Many phones have a glance setting that simply wakes the screen from time to time, but that really uses more system resources than it should. (fortheloveoftech.com)
You can also wake the screen by tapping on it, which displays the watch face for 15 seconds by default, but this can be extended to 70 seconds. (howtogeek.com)
Thankfully, you can wake the screen by pressing the touch - sensitive panel if the screen has timed out, rather than locking. (techradar.com)