base-ring and frame-ring
collector ring (slip-ring)
column-ring beam joint with shear ring bars
outside ring in-feed system ring
ring of n×n matrices over ring R
ring out the old year and ring in the new
Riser-ring and Ring Module
short-proof ring (arcing ring)
the Western Ring Road Sector of Central Ring Road
anal ring hairs anal ring setae
Air-on-oil caliper-disk brake