Primarily, the -plex suffix applied to the argument $$n$$ represents the number $$10^n$$. The definition was proposed by Rudy Rucker in a book "Mind tools" in 1987 by generalizing the definition of googolplex. However, the suffix has been occasionally used for other purposes.

Aarex Tiaokhiao coined the alternate term -noogol for this prefix.

$$10^{10^{n}}$$ may be notated -plexplex or, more commonly, -duplex. Similarly, $$10^{10^{10^{n}}}$$ is -triplex. In general, for a Latin prefix n, -n-plex means n copies of the -plex suffix.

$$10^{-n}$$, conversely, is called n-minex (wordplay on plus = plex, so minus = minex), therefore the number 10-googol is called googolminex. Sbiis Saibian used the suffix -minutia for some of his numbers. For example a gogol-minutia is 10-50.

In the works of Jonathan Bowers, -plex has a more general and less formal definition: if a number n is $$f(10, 100)$$ where $$f$$ is some googological function, then n-plex is defined as $$f(10, n)$$. For example, giggol = $$10\uparrow\uparrow 100$$, and giggolplex is not $$10^{\text{giggol}} = 10 \uparrow \uparrow 101$$ (which is called giggolunex) but is instead defined as $$10\uparrow\uparrow\text{giggol}$$. There are some exceptions to this rule, for instance golapulusplex. Sbiis Saibian circumvents this subjective definition by defining new prefixes such as -dex and -threx. For his googolisms in Cascading-E and higher components of his system, he uses the word grand analogous to Bowers' usage of -plex (for example, grand tethrathoth).

Googology Wiki user Hyp cos uses -plex in yet another way. Before dimensol, if n = s(3,2,...), then n-plex = s(3,3,...), n-biplex = s(3,4,...), n-triplex = s(3,5,...) and n-quadriplex = s(3,6,...).

The -plex suffix is also used to name large numbers that The Game Theorists calculate, such as Marioplex and Minecraftplex, usually addressing the number of combinations of a certain mechanic in a specific video game.

## In googological notations

Notation Expression
BEAF $$\{10, n\}$$
Bird's array notation $$\{10, n\}$$
Hyper-E notation $$En$$
Fast-growing hierarchy Inbetween $$f_2(f_1(n))$$ and $$f_2(f_1^2(n))$$
Hardy hierarchy Inbetween $$H_{\omega^2+\omega}(n)$$ and $$H_{\omega^2+\omega 2}(n)$$
Slow-growing hierarchy $$g_{\omega^n}(10)$$