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dumb

2 ENTRIES FOUND:
1 dumb /ˈdʌm/ adjective
dumber; dumbest
1 dumb
/ˈdʌm/
adjective
dumber; dumbest
Britannica Dictionary definition of DUMB
informal
: not showing or having good judgment or intelligence : stupid or foolish
: not requiring or resulting from intelligence
: not able to speak especially after being shocked or surprised
see also dumbstruck
old-fashioned + offensive : not having the ability to speak
◊ This sense is offensive and should be avoided. When a single word to describe someone who lacks the ability to speak is called for, the word mute is used instead.

— dumbness

noun, informal [noncount]
2 dumb /ˈdʌm/ verb
dumbs; dumbed; dumbing
2 dumb
/ˈdʌm/
verb
dumbs; dumbed; dumbing
Britannica Dictionary definition of DUMB

dumb down

[phrasal verb]
dumb down (something) or dumb (something) down usually disapproving
: to make (something) easier to understand
: to make (a group of people) less intelligent or educated

— dumbing down

noun [noncount]