From Archwiki > xrandr:
Tip: Both GDM and SDDM have startup scripts that are executed when X is initiated. For GDM, these are in /etc/gdm/, while for SDDM this is done at /usr/share/sddm/scripts/Xsetup. This method requires root access and mucking around in system configuration files, but will take effect earlier in the startup process than using xprofile.
In French, oursin (urchin) seems to be the diminutive of ours, which means bear. So oursin means something like “little bear”.