Yes, in the context that you're using it, it means.
Red Green Blue Intensity
RGBi can also refer to the type of 'Connection' between devices, for example, an RGBi cable from your Computer to your Monitor.

This is a D-Sub cable, most often used between your monitor and computer.
Pin Name Dir Description
1 GND --- Ground
2 GND --- Ground
3 R --> Red
4 G --> Green
5 B --> Blue
6 I --> Intensity
7 VIDEO --> Composite Video
8 HSYNC --> Horizontal Sync
9 VSYNC --> Vertical Sync