console frame buffer font is just a fancy way of saying pixel font.

console means that it is to be used with a console [1] or terminal emulator[2]. Traditionally terminal emulators used bitmap fonts, but modern versions support vector fonts as well. frame buffer [3] just means that it is a bitmap font like the ones used in traditional frame buffer consoles.

[1] https://en.wikipedia.org/wiki/System_console

[2] https://en.wikipedia.org/wiki/Terminal_emulator

[3] https://en.wikipedia.org/wiki/Framebuffer

It's referring to a kind of display driver in which frames are rendered as bitmaps into memory then that bitmap will be rendered to a screen. Fonts for such drivers are, AFAIK, always bitmap fonts.

https://en.wikipedia.org/wiki/Linux_framebuffer

A bitmap font that can be used in the Linux console.