Dull (?), a. [Compar. Duller (?); superl. Dullest.] [AS. dol foolish; akin to gedwelan to err, D. dol mad, dwalen to wander, err, G. toll mad, Goth. dwals foolish, stupid, cf. Gr. &unr_; turbid, troubled, Skr. dhvr to cause to fall. Cf. Dolt, Dwale, Dwell, Fraud.] 1. Slow of understanding; wanting readiness of apprehension; stupid; doltish; blockish. “Dull at classical learning.” Thackeray.
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She is not bred so dull but she can learn. Shak.
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2. Slow in action; sluggish; unready; awkward.
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This people's heart is waxed gross, and their ears are dull of hearing. Matt. xiii. 15.
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O, help my weak wit and sharpen my dull tongue. Spenser.
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3. Insensible; unfeeling.
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Think me not
So dull a devil to forget the loss
Of such a matchless wife. Beau. & Fl.
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4. Not keen in edge or point; lacking sharpness; blunt. “Thy scythe is dull.” Herbert.
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5. Not bright or clear to the eye; wanting in liveliness of color or luster; not vivid; obscure; dim; as, a dull fire or lamp; a dull red or yellow; a dull mirror.
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6. Heavy; gross; cloggy; insensible; spiritless; lifeless; inert. “The dull earth.” Shak.
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As turning the logs will make a dull fire burn, so changes of study a dull brain. Longfellow.
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7. 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.
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Along life's dullest, dreariest walk. Keble.

Syn. -- Lifeless; inanimate; dead; stupid; doltish; heavy; sluggish; sleepy; drowsy; gross; cheerless; tedious; irksome; dismal; dreary; clouded; tarnished; obtuse. See Lifeless.
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Dull, v. i. To become dull or stupid. Rom. of R.
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