toneless (adj.)
- achromatic
- achromic
- anemic
- ashen
- ashy
- bloodless
- cadaverous
- colorless
- dead
- dim
- dimmed
- dingy
- dull
- etiolated
- exsanguine
- faded
- faint
- fallow
- flat
- ghastly
- gray
- haggard
- hueless
- lackluster
- leaden
- livid
- lurid
- lusterless
- mat
- mealy
- monotone
- monotonic
- muddy
- neutral
- pale
- pale-faced
- pallid
- pasty
- sallow
- sickly
- sonorous
- sounded
- sounding
- tonal
- uncolored
- wan
- washed-out
- waxen
- weak
- white