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

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, səˈlɪdɪtɪ /

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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Related Words

See firm ¹.

Other Word Forms

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

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

When this happened, their Bayern team-mates would move into the back-line to maintain a solid defensive shape.

From BBC • Apr. 15, 2026

“Here we also expect to see solid demand as the curve is steep in this segment and the greenium is modest,” the chief analyst says.

From The Wall Street Journal • Apr. 14, 2026

The shelters - rectangular red-brick buildings with a solid concrete roof and no windows - could accommodate up to 100 people.

From BBC • Apr. 14, 2026

Overall, it’s a solid report, and Fastenal said the “broader market conditions have begun to improve.”

From Barron's • Apr. 13, 2026

Natalie tumbled along the rough rooftop, trying to grab hold of something, anything, and then suddenly the solid ground underneath her was gone and she was underwater again.

From "Two Degrees" by Alan Gratz

Related Words

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