dull (e.g. a knife); blunt; thickheaded; obtuse; dull (sound, color, etc.); dim (light)
to become blunt; to grow dull; to become less capable; to weaken; to falter
dull sound; muffled sound
dark gray; dark grey; donjiki (clerical dress)
to become insensitive; to become less perceptive; to lose one's touch; to get out of practice
to waver in one's resolution
to blunt; to dull; to weaken
dim-witted; airheaded; bird-brained; dim; dullard; blockheaded
dullard (gen. from not picking up on other people's feelings)
insensitive; thick-skinned