DULL a.
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. Along life's dullest, dreariest walk. Keble.
INSIPID a.
Wanting in spirit, life, or animation; uninteresting; weak; vapid; flat; dull; heavy; as, an insipid woman; an insipid composition. Flat, insipid, and ridiculous stuff to him. South. But his wit is faint, and his salt, if I may dare to say so, almost insipid. Dryden.