(adj): lacking vitality or spirit; lifeless
(adj): dull and slow-moving and stolid; like an ox
(adj): lacking in liveliness or charm or surprise
(adj): lacking lightness or liveliness
(adj): tediously repetitious or lacking in variety
(adj): lacking brilliance or vitality
(adj): vs. bright) -- (emitting or reflecting very little light
(adj): not reflecting light; not glossy
(adj): lacking luster or shine
(adj): not brilliant or glaring
(adj): being or made softer or less loud or clear
(adj): vs. loud) -- ((of sound) relatively low in volume
(adj): so lacking in interest as to cause mental weariness
(adj): vs. interesting) -- (arousing no interest or attention or curiosity or excitement
(adj): (of color) very low in saturation; highly diluted
(adj): vs. saturated) -- ((of color) not chromatically pure; diluted
(adj): vs. sharp) -- (not keenly felt
(adj): made or become less intense
(adj): slow to learn or understand; lacking intellectual acuity
(adj): vs. smart) -- (lacking or marked by lack of intellectual acuity
(adj): (of business) not active or brisk
(adj): vs. active) -- (lacking activity; lying idle or unused
(adj): vs. sharp) -- (not having a sharp edge or point
(adj): used of a knife or other blade; not sharp
(adj): made dull or blunt
(adj): lacking a cutting edge
(adj): not sharpened
(adj): blunted in responsiveness or sensibility
(adj): vs. sensitive) -- (deficient in human sensibility; not mentally or morally sensitive
(adj): not clear and resonant; sounding as if striking with or against something relatively soft
(adj): vs. reverberant), nonresonant -- (not reverberant; lacking a tendency to reverberate
(adj): darkened with overcast
(adj): vs. clear) -- (full of or covered with clouds
(v): make dull in appearance
(v): cause to change; make different; cause a transformation
(v): become dull or lusterless in appearance; lose shine or brightness
(v): undergo a change; become different in essence; losing one's or its original nature
(v): deaden (a sound or noise), especially by wrapping
(v): make (images or sounds) soft or softer
(v): make numb or insensitive
(v): cause not to be sensitive
(v): make dull or blunt
(v): cause to change; make different; cause a transformation
(v): become less interesting or attractive
(v): undergo a change; become different in essence; losing one's or its original nature
(v): make less lively or vigorous
(v): become weaker
