The act of waiting in real-time. Games that feature this idea will at some point force the player to wait for a specific amount of time to pass before continuing on. Some games allow the player to continue progressing even if they refuse to wait, while others will force the player to start over if he or she runs out of patience and attempts to progress.
In EarthBound, the player must at one point gain entrance to Master Belch's lair. To do so, Ness and his party must find the entrance behind a waterfall. When they are asked for a password, the answer is to do nothing for three minutes and wait for access to be granted.
One example of this idea in action takes place early on in the game Chrono Trigger. While attending the fair with Marle, Marle at one point stops in front of a booth and tells the player's character Crono to wait up. If the player waits for Marle to finish, she'll thank Crono and the game will continue. If the player becomes impatient and tries to move before she's done, the rude act comes back to haunt Crono later in the game.
The most extreme example of real-time waiting appears in the game Takeshi's Challenge. This Japan-only Famicom release created by actor and director Takeshi Kitano is defined by a series of outlandish tasks that the player must perform in order to continue. One of these tasks asks the player to hold down a button on the controller for four hours. The easiest way to complete this particular challenge is by placing a book or other object on the button and waiting for enough time to pass. Another (easier) example is that to reveal the location of a treasure on a map, the player must wait an hour for the image to appear. Pressing anything will destroy the map, forcing the player to get it again.