The 36 words below comprise a set of eight related to eight, a set of seven related to seven, a set of six related to six, and so on. Which word belongs to the set of one?
ABILITY ALTO ARCHING BANANA BONE BOSC
BRAN COMPUTER CONFERENCE CONY CRAG DENT
DOG ENABLE FILE FLING GLENDA GLUE
GRASS GUN IMPOSE JOE LAZY MODEL
MORE NATURAL NEON PERCY POLLOCK RASH
SCRIPT SECRET SHIRLEY STRING VIAL VISOR
(With apologies to the GCHQ Kristmas Kwiz / puzzle book compilers, with whom this puzzle format originates.)