Dull vs. Flat — What's the Difference?

Arousing little interest; lacking liveliness; boring

Having a level surface; without raised areas or indentations

Not brisk or rapid; sluggish

Lacking emotion; dull and lifeless

Not having a sharp edge or point; blunt

(of a sparkling drink) having lost its effervescence

Not intensely or keenly felt

(of a fee, wage, or price) the same in all cases, not varying with changed conditions or in particular cases

Not bright, vivid, or shiny

(of musical sound) below true or normal pitch.

Cloudy or overcast

Relating to flat racing

Not clear or resonant

In or to a horizontal position

Intellectually weak or obtuse; stupid.

Completely; absolutely

Lacking responsiveness or alertness; insensitive

Below the true or normal pitch of musical sound

Dispirited; depressed

The flat part of something

To make or become dull.

An upright section of stage scenery mounted on a movable frame.

Lacking the ability to cut easily; not sharp.

A flat tyre

Boring; not exciting or interesting.

Flat racing.

Not shiny; having a matte finish or no particular luster or brightness.

A musical note lowered a semitone below natural pitch.

Not bright or intelligent; stupid; having slow understanding.

A set of rooms forming an individual residence, typically on one floor and within a larger building containing a number of such residences.

Sluggish, listless.

Lower (a note) by a semitone

Cloudy, overcast.

Make flat; flatten

Insensible; unfeeling.

Live in or share a flat

Heavy; lifeless; inert.

Having a smooth, even surface

(of pain etc) Not intense; felt indistinctly or only slightly.

Having a relatively broad level surface in relation to thickness or depth

Not clear, muffled.

Being in horizontal position; lying down

(transitive) To render dull; to remove or blunt an edge or something that was sharp.

Being without slope or curvature

(transitive) To soften, moderate or blunt; to make dull, stupid, or sluggish; to stupefy.

Having a low heel or no heel

(intransitive) To lose a sharp edge; to become dull.

Free of qualification; absolute

To render dim or obscure; to sully; to tarnish.

Fixed; unvarying

Slow of understanding; wanting readiness of apprehension; stupid; doltish; blockish.

Lacking interest or excitement; dull

Slow in action; sluggish; unready; awkward.

Lacking in flavor

Insensible; unfeeling.

Having lost effervescence or sparkle

Not keen in edge or point; lacking sharpness; blunt.

Deflated. Used of a tire.

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.

Electrically discharged. Used of a storage battery.

Heavy; gross; cloggy; insensible; spiritless; lifeless; inert.

Of or relating to a horizontal line that displays no ups or downs and signifies the absence of physiological activity

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.

Of or relating to a hierarchy with relatively few tiers or levels

To deprive of sharpness of edge or point.

Commercially inactive; sluggish

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

Unmodulated; monotonous

To render dim or obscure; to sully; to tarnish.

Lacking variety in tint or shading; uniform

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

Not glossy; matte

To become dull or stupid.

Being below the correct pitch.

Make dull in appearance;

Being one half step lower than the corresponding natural key

Become dull or lusterless in appearance; lose shine or brightness;

Designating the vowel a as pronounced in bad or cat.

Deaden (a sound or noise), especially by wrapping

(Nautical) Taut. Used of a sail.

Make numb or insensitive;

(Informal) Having small breasts.

Make dull or blunt;

Level with the ground; horizontally.

Become less interesting or attractive

On or up against a flat surface; at full length.

Make less lively or vigorous;

So as to be flat.

Lacking in liveliness or animation;

Directly; completely

Emitting or reflecting very little light;

Exactly; precisely

Being or made softer or less loud or clear;

(Music) Below the intended pitch.

So lacking in interest as to cause mental weariness;

(Business) Without interest charge.

(of color) very low in saturation; highly diluted;

A flat surface or part.

Not keenly felt;

Often flats A stretch of level ground

Slow to learn or understand; lacking intellectual acuity;

A shallow frame or box for seeds or seedlings.

(of business) not active or brisk;

A movable section of stage scenery, usually consisting of a wooden frame and a decorated panel of wood or cloth.

Not having a sharp edge or point;

A flatcar.

Blunted in responsiveness or sensibility;

A deflated tire.

Not clear and resonant; sounding as if striking with or against something relatively soft;

A shoe with a flat heel.

Darkened with overcast;

A large flat piece of mail.

A horse that competes in a flat race. Also called runner.

A sign (♭) used to indicate that a note is to be lowered by a semitone.

A note that is lowered a semitone.

(Football) The area of the field to either side of an offensive formation.

An apartment on one floor of a building.

(Archaic) A story in a house.

To make flat; flatten.

(Music) To lower (a note) a semitone.

To sing or play below the proper pitch.

Having no variations in height.

In a horizontal line or plane; not sloping.

Smooth; having no protrusions, indentations or other surface irregularities, or relatively so.

(slang) Having small or invisible breasts and/or buttocks.

Without variation in level, quantity, value, tone etc.

At a consistently depressed level; consistently lacklustre.

Of fees, fares etc., fixed; unvarying.

Without variations in pitch.

(of colours) Without variation in tone or hue (uniform), and dull (not glossy).

(figurative) Lacking liveliness or action; depressed; uninteresting; dull and boring.

Lacking in depth, substance, or believability; underdeveloped; one-dimensional.

Lowered by one semitone.

(music) Of a note or voice, lower in pitch than it should be.

Absolute; downright; peremptory.

(of a tire or other inflated object) Deflated, especially because of a puncture.

(of a carbonated drink) With all or most of its carbon dioxide having come out of solution so that the drink no longer fizzes or contains any bubbles.

(wine) Lacking acidity without being sweet.

(of a battery) Unable to emit power; dead.

Without spin; spinless.

Sonant; vocal, as distinguished from a sharp (non-sonant) consonant.

(grammar) Not having an inflectional ending or sign, such as a noun used as an adjective, or an adjective as an adverb, without the addition of a formative suffix; or an infinitive without the sign "to".

Having a head at a very obtuse angle to the shaft.

Flattening at the ends.

(of measurements of time) Exact.

So as to be flat.

Bluntly.

(of accurately measured timings) Exactly, precisely.

Used to emphasize the smallness of the measurement.

Completely.

Directly; flatly.

Without allowance for accrued interest.

An area of level ground (sometimes covered with water).

(in the phrase 'the flat') Level ground in general.

Level horse-racing ground, as contrasted with courses incorporating jumps, or the racing done on such ground.

The area in the centre of a racecourse.

(music) A note played a semitone lower than a natural, denoted by the symbol ♭ placed after the letter representing the note (e.g., B♭) or in front of the note symbol (e.g. ♭♪).

A flat tyre/flat tire.

(in the plural) A type of ladies' shoe with a very low heel.

(in the plural) A type of flat-soled running shoe without spikes.

(painting) A thin, broad brush used in oil and watercolour painting.

The flat part of something:

(swordfighting) The flat side of a blade, as opposed to the sharp edge.

The palm of the hand, with the adjacent part of the fingers.

A wide, shallow container or pallet.

(mail) A large mail piece measuring at least 8 1/2 by 11 inches, such as catalogs, magazines, and unfolded paper enclosed in large envelopes.

A railroad car without a roof, and whose body is a platform without sides; a platform car or flatcar.

A flat-bottomed boat, without keel, and of small draught.

(geometry) A subset of n-dimensional space that is congruent to a Euclidean space of lower dimension.

A straw hat, broad-brimmed and low-crowned.

A flat sheet for use on a bed.

(publishing) A flat, glossy children's book with few pages.

A platform on a wheel, upon which emblematic designs etc. are carried in processions.

(mining) A horizontal vein or ore deposit auxiliary to a main vein; also, any horizontal portion of a vein not elsewhere horizontal.

(technical, theatre, stagecraft) A rectangular wooden structure covered with masonite, lauan, or muslin, often produced in standard modules, that is used to build wall surfaces on stage. Flats can be painted and outfitted with doors and/or windows to depict a building or other part of a scene. It's a hard-surfaced alternative to a backcloth orbackdrop.

(entomology) Any of various hesperiid butterflies that spread their wings open when they land.

(historical) An early kind of toy soldier having a flat design.

(obsolete) A dull fellow; a simpleton.

(optics) A flat (i.e. plane) mirror

A cheater's die with the edges shaved to make certain rolls more likely.

An apartment, usually on one level and usually consisting of more than one room.

(poker slang) To make a flat call; to call without raising.

(intransitive) To become flat or flattened; to sink or fall to an even surface.

To fall from the pitch.

To depress in tone, as a musical note; especially, to lower in pitch by half a tone.

To make flat; to flatten; to level.

To render dull, insipid, or spiritless; to depress.

To beat or strike; pound

(transitive) To dash or throw

(intransitive) To dash, rush

Having an even and horizontal surface, or nearly so, without prominences or depressions; level without inclination; plane.

Lying at full length, or spread out, upon the ground; level with the ground or earth; prostrate; as, to lie flat on the ground; hence, fallen; laid low; ruined; destroyed.

Wanting relief; destitute of variety; without points of prominence and striking interest.

Tasteless; stale; vapid; insipid; dead; as, fruit or drink flat to the taste.

Unanimated; dull; uninteresting; without point or spirit; monotonous; as, a flat speech or composition.

Lacking liveliness of commercial exchange and dealings; depressed; dull; as, the market is flat.

Clear; unmistakable; peremptory; absolute; positive; downright.

Below the true pitch; hence, as applied to intervals, minor, or lower by a half step; as, a flat seventh; A flat.

Sonant; vocal; - applied to any one of the sonant or vocal consonants, as distinguished from a nonsonant (or sharp) consonant.

Having a head at a very obtuse angle to the shaft; - said of a club.

Not having an inflectional ending or sign, as a noun used as an adjective, or an adjective as an adverb, without the addition of a formative suffix, or an infinitive without the sign to. Many flat adverbs, as in run fast, buy cheap, are from AS. adverbs in -ë, the loss of this ending having made them like the adjectives. Some having forms in ly, such as exceeding, wonderful, true, are now archaic.

Flattening at the ends; - said of certain fruits.

In a flat manner; directly; flatly.

Without allowance for accrued interest.

A level surface, without elevation, relief, or prominences; an extended plain; specifically, in the United States, a level tract along the along the banks of a river; as, the Mohawk Flats.

A level tract lying at little depth below the surface of water, or alternately covered and left bare by the tide; a shoal; a shallow; a strand.

Something broad and flat in form

The flat part, or side, of anything; as, the broad side of a blade, as distinguished from its edge.

A floor, loft, or story in a building;

A horizontal vein or ore deposit auxiliary to a main vein; also, any horizontal portion of a vein not elsewhere horizontal.

A dull fellow; a simpleton; a numskull.

A character [$] before a note, indicating a tone which is a half step or semitone lower.

A homaloid space or extension.

To make flat; to flatten; to level.

To render dull, insipid, or spiritless; to depress.

To depress in tone, as a musical note; especially, to lower in pitch by half a tone.

To become flat, or flattened; to sink or fall to an even surface.

To fall form the pitch.

A level tract of land

A shallow box in which seedlings are started

A musical notation indicating one half step lower than the note named

Freight car without permanent sides or roof

A deflated pneumatic tire

Scenery consisting of a wooden frame covered with painted canvas; part of a stage setting

A suite of rooms usually on one floor of an apartment house

Having a horizontal surface in which no part is higher or lower than another;

Having no depth or thickness

Not modified or restricted by reservations;

Stretched out and lying at full length along the ground;

Lacking contrast or shading between tones

Lowered in pitch by one chromatic semitone;

Flattened laterally along the whole length (e.g., certain leafstalks or flatfishes)

Lacking taste or flavor or tang;

Lacking stimulating characteristics; uninteresting;

Having lost effervescence;

Not increasing as the amount taxed increases

Not made with leavening;

Parallel to the ground;

Without pleats

Lacking the expected range or depth; not designed to give an illusion or depth;

(of a tire) completely or partially deflated

Not reflecting light; not glossy;

Lacking variety in shading;

At full length;

With flat sails;

Below the proper pitch;

Against a flat surface;

In a forthright manner; candidly or frankly;

Wholly or completely;