MySQL tables/databases into different disks
I'm not aware of a specific term for this practice but you can specify different data and/or index dirs using the create table syntax.

This only works for MyISAM tables and your OS must support symlinks.

In my practice though, we generally just segment sets databases into their own LV. These are generally a segment per functional application.  Having a single logical volume with all the tables actually in there it's easier to keep track of an manage disk space for each DB.

Those LVs though, are generally in a RAID 10 config to help balance IO.