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
verb
dulled; 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.
Keep scrolling for more
Keep scrolling for more
Keep scrolling for more
Keep scrolling for more
Test Your Vocabulary
The Exceptions Quiz III
-
- Which of these words does not mean "nonsense"?

Test your knowledge - and maybe learn something along the way.
TAKE THE QUIZ
Spell words. Make bears.
TAKE THE QUIZLove words? Need even more definitions?
Merriam-Webster unabridged
Words at Play
Ask the Editors
Share dull
Time Traveler for dull
The first known use of dull was in the 13th century
See more words from the same century