Definition of dull
(Entry 1 of 2)
1 : tedious, uninteresting dull lectures
2 : lacking sharpness of edge or point
a dull knife
3a : not resonant or ringing
a dull booming sound
b : lacking in force, intensity, or sharpness
a dull ache
4 : lacking brilliance or luster a dull finish
5 : cloudy dull weather
7 : mentally slow : stupid
8a : slow in perception or sensibility : insensible somewhat dull of hearing dull to what went on about her— Willa Cather
b : lacking zest (see zest sense 2) or vivacity : listless a dull performance
9 : slow in action : sluggish dull markets
dull
verbdulled; dulling; dulls
Definition of dull (Entry 2 of 2)
: to make dull dull a knife's edge
: to become dull
The blade dulled with use.
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Time Traveler for dull
The first known use of dull was in the 13th century
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