Dull, v. t. [imp. & p. p. Duller (?); p. pr. & vb. n. Dulling.] 1. To deprive of sharpness of edge or point. "This . . . dulled their swords." Bacon.

Borrowing dulls the edge of husbandry.

2. To make dull, stupid, or sluggish; to stupefy, as the senses, the feelings, the perceptions, and the like.

Those [drugs] she has
Will stupefy and dull the sense a while.

Use and custom have so dulled our eyes.

3. To render dim or obscure; to sully; to tarnish. "Dulls the mirror." Bacon.

4. To deprive of liveliness or activity; to render heavy; to make inert; to depress; to weary; to sadden.

Attention of mind . . . wasted or dulled through continuance.

Dull, v. i. To become dull or stupid. Rom. of R.

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. ? 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.

She is not bred so dull but she can learn.

2. Slow in action; sluggish; unready; awkward.

This people's heart is waxed gross, and their ears are dull of hearing.
Matt. xiii. 15.

O, help my weak wit and sharpen my dull tongue.

3. Insensible; unfeeling.

Think me not
So dull a devil to forget the loss
Of such a matchless wife.
Beau. & Fl.

4. Not keen in edge or point; lacking sharpness; blunt. "Thy scythe is dull." Herbert.

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.

6. Heavy; gross; cloggy; insensible; spiritless; lifeless; inert. "The dull earth." Shak.

As turning the logs will make a dull fire burn, so changes of study a dull brain.

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.

Along life's dullest, dreariest walk.

Syn. -- Lifeless; inanimate; dead; stupid; doltish; heavy; sluggish; sleepy; drowsy; gross; cheerless; tedious; irksome; dismal; dreary; clouded; tarnished; obtuse. See Lifeless.