dullness (n.)
- abruptness
- acedia
- achromaticity
- achromatism
- adynamia
- aloofness
- analgesia
- anemia
- anesthesia
- angst
- anguish
- anxiety
- apathy
- aridity
- aridness
- ashiness
- asininity
- ataraxia
- atony
- autism
- barrenness
- blah
- blahs
- bluffness
- bluntness
- boorishness
- boredom
- boringness
- cachexia
- cachexy
- callousness
- catatonia
- cheerlessness
- chill
- chilliness
- coldness
- colorlessness
- coma
- comatoseness
- commonness
- commonplaceness
- coolness
- cowardice
- crassness
- crudeness
- deadness
- debilitation
- debility
- denseness
- density
- detachment
- dimness
- discomfort
- discomposure
- discontent
- disinterest
- dislike
- dispassion
- dispassionateness
- displeasure
- disquiet
- dissatisfaction
- drabness
- dread
- drowsiness
- dryness
- dumbness
- emotionlessness
- emptiness
- enervation
- ennui
- etiolation
- faintness
- fairness
- fatigue
- feebleness
- flabbiness
- flaccidity
- flatness
- frigidity
- frostiness
- ghastliness
- gray
- grayness
- grimness
- grossness
- heartlessness
- heaviness
- hebetude
- hopelessness
- iciness
- immovability
- impassiveness
- impassivity
- imperturbability
- imperturbableness
- impotence
- inconsiderateness
- indifference
- infertility
- inquietude
- insensibility
- insensitiveness
- insensitivity
- insentience
- insipidness
- insouciance
- joylessness
- languor
- lassitude
- lenitude
- lethargy
- lifelessness
- lightness
- listlessness
- lividity
- lividness
- long-windedness
- malaise
- mediocrity
- moderateness
- modestness
- modesty
- muddiness
- narcosis
- nausea
- nonchalance
- numbness
- objectivity
- obtuseness
- opacity
- oscitancy
- painfulness
- paleness
- pallidity
- pallidness
- pallor
- passiveness
- passivity
- patience
- phlegm
- plainness
- prolixity
- prosaicness
- prosiness
- prostration
- resignation
- respectability
- sallowness
- savorlessness
- self-absorption
- sleep
- sleepiness
- sloth
- slothfulness
- slowness
- sluggishness
- slumber
- soberness
- softness
- somberness
- somnolence
- sopor
- sottishness
- spiritlessness
- spleen
- staidness
- staleness
- steadiness
- stoicism
- stolidity
- stuffiness
- stupefaction
- stupidity
- stupor
- tastelessness
- tediousness
- tedium
- tiresomeness
- torpidity
- torpidness
- torpor
- uncomfortableness
- unconcern
- uncreativeness
- unease
- uneasiness
- unfeelingness
- unhappiness
- unoriginality
- unperceptiveness
- unresponsiveness
- unsusceptibility
- vapidity
- wanness
- weakness
- weariness
- withdrawal
- withdrawnness
- world-weariness
