Thousalogue

Thousalogue is a base googolism of the second order Hyper-L notation invented by JTOnstead20. It is defined as L((3)) in the notation. This means the following:

Take the reverse Log function of 3 to get 1000. Then use the double parenthesis to build a power tower starting with 10^1000^1000 and going 1000 units high. This is roughly equivalent to 1000^^1000 with ^ being an up arrow in arrow notation.

Sources:
JTO's Hyper-L Notation