Bathroom accessory (5)
(Other definitions for scale that I've seen before include "Relative size (of something)" , "See 23" , "Ratio of, say, map to reality" , "Series of notes in an octave" , "Notes < magnitude" .)
(Other definitions for shower curtain that I've seen before include "Bathroom barrier" , "Bathroom protector" , "Bathroom hang-up?" , "Splash preventer" , "We run chariots (anag) -- bathroom fixture" .)