Glocillion

The glocillion is equal to $$10^{3 \cdot 10^{3 \cdot 10^{3 \cdot \text{nonillion}}} + 3}$$, or $$10^{3 \cdot 10^{3 \cdot 10^{3 \cdot 10^{30}}} + 3}$$. The term was coined by Jonathan Bowers.

Etymology
The name of this number is based on the phrase "Glo bular C luster" and the suffix "-illion".