Furnishing little delight, spirit, or variety; uninteresting; tedious; cheerless; gloomy; melancholy; depressing; as, a dull story or sermon; a dull occupation or period; hence, cloudy; overcast; as, a dull day.
To deprive of sharpness of edge or point.
To make dull, stupid, or sluggish; to stupefy, as the senses, the feelings, the perceptions, and the like.
To render dim or obscure; to sully; to tarnish.
To deprive of liveliness or activity; to render heavy; to make inert; to depress; to weary; to sadden.
dull in Dutch is onnozel, dom, flauw, simpel
dull in French is terne, fade, obtus
dull in Italian is appannato, insipido
dull in Latin is bardus, stolidus, piger pigra pigrum
dull in Spanish is embotado, lasto, soso