solid

American  

[sol-id] / ˈsɒl ɪd /

adjective

solider, solidest

1. having three dimensions (length, breadth, and thickness), as a geometrical body or figure.

   Synonyms:

   cubic

   Antonyms:

   flat

2. of or relating to bodies or figures of three dimensions.

3. having the interior completely filled up, free from cavities, or not hollow.

   a solid piece of chocolate.

4. without openings or breaks.

   a solid wall.

5. firm, hard, or compact in substance.

   solid ground.

   Synonyms:

   dense

6. having relative firmness, coherence of particles, or persistence of form, as matter that is not liquid or gaseous.

   solid particles suspended in a liquid.

   Synonyms:

   firm, cohesive

   Antonyms:

   loose

7. pertaining to such matter.

   Water in a solid state is ice.

8. dense, thick, or heavy in nature or appearance.

   solid masses of cloud.

9. not flimsy, slight, or light, as buildings, furniture, fabrics, or food; substantial.

   Synonyms:

   sound

10. of a substantial character; not superficial, trifling, or frivolous.

    a solid work of scientific scholarship.

11. without separation or division; continuous.

    a solid row of buildings.

    Synonyms:

    unbroken

    Antonyms:

    divided

12. whole or entire.

    one solid hour.

13. forming the whole; consisting entirely of one substance or material.

    solid gold.

14. uniform in tone or shades, as a color.

    a solid blue dress.

15. real or genuine.

    solid comfort.

16. sound or reliable, as reasons or arguments.

    solid facts.

17. sober-minded; fully reliable or sensible.

    a solid citizen.

18. financially sound or strong.

    Our company is solid.

    Synonyms:

    solvent

19. cubic.

    A solid foot contains 1,728 solid inches.

20. written without a hyphen, as a compound word.

21. having the lines not separated by leads, or having few open spaces, as type or printing.

22. thorough, vigorous, great, big, etc. (with emphatic force, often aftergood ).

    a good solid blow.

    Synonyms:

    strong

23. firmly united or consolidated.

    a solid combination.

24. united or unanimous in opinion, policy, etc.

    Antonyms:

    divided

25. on a friendly, favorable, or advantageous footing (often preceded byin ).

    He was in solid with her parents.

26. Slang. excellent, especially musically.

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noun

• solids
  plural

1. a body or object having three dimensions (length, breadth, and thickness).

2. a solid substance or body; a substance exhibiting rigidity.

idioms

1. do (someone) a solid, to help out, be supportive, or do a favor for.

   Do him a solid and second his nomination.

solid British  

/ ˈsɒlɪd /

adjective

1. of, concerned with, or being a substance in a physical state in which it resists changes in size and shape Compare liquid gas

2. consisting of matter all through

3. of the same substance all through

   solid rock

4. sound; proved or provable

   solid facts

5. reliable or sensible; upstanding

   a solid citizen

6. firm, strong, compact, or substantial

   a solid table

   solid ground

7. (of a meal or food) substantial

8. (often postpositive) without interruption or respite; continuous

   solid bombardment

9. financially sound or solvent

   a solid institution

10. strongly linked or consolidated

    a solid relationship

11. geometry having or relating to three dimensions

    a solid figure

    solid geometry

12. (of a word composed of two or more other words or elements) written or printed as a single word without a hyphen

13. printing with no space or leads between lines of type

14. unanimously in favour of

15. (of a writer, work, performance, etc) adequate; sensible

16. of or having a single uniform colour or tone

17. informal excessive; unreasonably strict

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noun

1. geometry

   1. a closed surface in three-dimensional space

   2. such a surface together with the volume enclosed by it

2. a solid substance, such as wood, iron, or diamond

3. (plural) solid food, as opposed to liquid

solid Scientific  

/ sŏl′ĭd /

1. Physics One of four main states of matter, in which the molecules vibrate about fixed positions and cannot migrate to other positions in the substance. Unlike a gas or liquid, a solid has a fixed shape, and unlike a gas, a solid has a fixed volume. In most solids (with exceptions such as glass), the molecules are arranged in crystal lattices of various sizes.

2. Mathematics A geometric figure that has three dimensions.

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solid Cultural  

1. A phase of matter characterized by the tight locking of atoms into rigid structures that resist deforming by outside forces.

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Synonym Usage

See firm ¹.

Other Word Forms

Derived Forms

• solidity
  noun
• solidness
  noun
• subsolid
  noun
• unsolidness
  noun
• half-solid
  adjective
• nonsolid
  adjective
• transsolid
  adjective
• unsolid
  adjective
• nonsolidly
  adverb
• solidly
  adverb
• unsolidly
  adverb

Inflected Forms

Nouns

• solids
  plural

Etymology

Origin of solid

First recorded in 1350–1400; Middle English solide, from Old French solide, from Latin solidus “dense, compact”

Explanation

A solid, as opposed to a liquid or gas, has a size and shape to it. It doesn't flow like water or disappear into the air. At first glance, solid appears to be a simple word, but it really offers shades of meaning. A solid friend is dependable. If you give a solid performance, it was very good, though not quite great. Likewise, if you achieve a solid win, you win by a large, but not huge, majority. In a less figurative use, if a piece of chocolate is solid — as opposed to hollow — it is chocolate throughout.

Example Sentences

See Examples For:

solid solids solider solidest

Xi said Russia-Chinese ties had become "more solid" and that their "prospects will be even brighter", while Putin said cooperation was "successfully developing on all fronts".

From Barron's ● Sep. 1, 2026

“Lioness” and “MobLand” are violent fun, “Colin From Accounts” is terrific, ”Diarra From Detroit” is an underrated gem and the sports lineup is solid.

From MarketWatch ● Aug. 31, 2026

These include a fundamental question about the potential instability of the Thwaites Glacier due to the interaction of the ocean, ice and solid ground near where it meets the sea.

From Science Daily ● Aug. 30, 2026

Syracuse has a solid AA-minus bond rating, but S&P Global analysts revised their outlook to negative from stable last year citing weaker demand metrics compared with similarly rated peers.

From The Wall Street Journal ● Aug. 30, 2026

“The round ones are cream-filled, the square ones are solid chocolate, and the heart-shaped ones have nuts,” she explained.

From "The Seven Wonders of Sassafras Springs" by Betty G. Birney

It’s just like clockwork, if I have any solids during the day of the show, around song seven, I start burping.

From The Wall Street Journal ● Jul. 23, 2026

After college, he tried going West and struck gold with mining equipment that helped separate solids from slurry.

From The Wall Street Journal ● Jul. 4, 2026

Superionic materials are unusual because they behave partly like solids and partly like liquids.

From Science Daily ● Apr. 21, 2026

In solids, atoms form tightly packed lattice structures.

From Science Daily ● Apr. 19, 2026

The Pythagoreans were fascinated by the regular solids, symmetrical three-dimensional objects all of whose sides are the same regular polygon.

From "Cosmos" by Carl Sagan

There’s a scene in the 1981 Bill Murray film Stripes where a solider introduces himself to his colleagues as “Psycho,” though his real name is Francis.

From Slate ● Apr. 13, 2026

It was not clear whether the solider who died was among that toll.

From Barron's ● Mar. 12, 2026

Packaged in cosplay costumes — cowgirl, solider, even firefighter and pilot — we were supposed to see her as strong.

From Los Angeles Times ● Mar. 6, 2026

“When I first started, I almost gave up because it was very difficult, but she told me you must solider on,” he said.

From BBC ● Sep. 5, 2024

Only the day before, he confided to a friend that he “will have the fortune of receiving the greatest honor that can be given to a solider, that of dying for his country.”

From "At Last She Stood" by Erin Entrada Kelly

John Martin, in The New York Times, hailed it as an unlikely success, “the solidest foundation that has yet been laid for the development of the art of ballet in America.”

From New York Times ● Jul. 29, 2021

They persisted in seeing it as the solidest, most plausible candidate.

From The Guardian ● Feb. 28, 2011

But only about 5% are as potent as the tunes here--whoever inspired it, this is Lovett's solidest package in a long, ornery career.

From Time Magazine Archive

Frail but craggy in appearance, he struck people as the solidest of citizens.

From Time Magazine Archive

When they are real, they are not glass threads or frost-work, but the solidest thing we know.

From Essays by Ralph Waldo Emerson by Edna Henry Lee Turpin

Related Words

• decent
• genuine
• good
• real
• satisfactory
• satisfying
• serious