Greeking is the generic term for showing fake text
Greeking is a way to emphasize form over details. (Greek symbols aren't required)
Lorem ipsum is probably the most familiar kind of greeked text. It allows looking at text formatting without actually having any content. Designers and developers often use lorem ipsum text to imitate real words with little risk of anyone getting hung up on fake/incorrect content because it's obviously fake and incorrect.
1. The infamous hamburger menu icon
The hamburger menu icon represents a list of content without actually being content. This qualifies as Greeking and is used by Google Inbox (among others)

2. Facebook shows text wrapping around an image using abstract Greeking
The most abstract form of Greeking is using shaded rectangles as symbols in place of where actual content will go. The main advantage of using rectangular Greeking is that it works regardless of alphabet. Pretty much the only localization that needs to occur is flipping the image so the rectangles read left to right for certain locales.

3. Video games often use abstract Greeking as well
To reiterate the fact that something is written on a page or sign in a video game, designers will showing something resembling text. This happens on some items in the game Minecraft.
Video game greeked text is probably a limitation due to pixel resolution but it also allows adding many signs in a town without having to generate real text content for each one.

Shirt color: [_____] Shirt size: [_____ v ] Shirt text [______]
where it first has to ask the server for the fields (color, size, text are not hardcoded in the UI)