Dull

cego

(lacking the ability to cut easily; not sharp)

chato

(boring, not exciting or interesting — see also boring)

embotado

(lacking the ability to cut easily; not sharp)

enfadonho

(boring, not exciting or interesting — see also boring)

entediante

(boring, not exciting or interesting — see also boring)

estúpido

(not bright or intelligent)

fosco

(not shiny)

fusco

(not shiny)

fátuo

(not bright or intelligent)

idiota

(not bright or intelligent)

imbecil

(not bright or intelligent)

maçante

(boring, not exciting or interesting — see also boring)

nublado

(cloudy, overcast)

sem graça

(boring, not exciting or interesting — see also boring)

cegar

(to render dull)

desafiar

(to render dull)

desafiar

(to become dull)

suavizar

(to soften, moderate or blunt)