Translation guide
The English word "solid" has several distinct meanings. This guide organizes them by practical use, from physical states to abstract qualities, and provides natural Japanese equivalents for each.
Describing matter that is firm and stable in shape, not a liquid or gas.
The standard scientific/technical term for 'solid' as a state of matter. Used in formal contexts.
Water is a liquid, and ice is a solid.
Often used for 'solid' as opposed to liquid or powdered forms, e.g., solid food, solid fuel.
Solid fuel is convenient for camping.
General word for 'hard' or 'firm'. Can describe a solid object, but not the state of matter itself. Use with care: 固い means 'hard', not necessarily 'solid'.
Not a direct translation for 'solid' as a state; it means 'hard' or 'stiff'.
Describing an object that is strong, dense, and not easily broken or deformed.
Describes something sturdy, solidly built, durable. Common for furniture, buildings, vehicles.
Describing something that is not interrupted, such as a solid line, solid color, or solid hour.
Describing a person or thing that is trustworthy, sensible, and consistently good.
Means 'reliable', 'trustworthy'. The most direct equivalent for a solid person.
Describing something that is well-made, substantial, or satisfactory. Often used in phrases like 'solid meal' or 'solid performance'.
Again, very versatile. A 'solid meal' can be しっかりした食事.
Describing a group that is fully united in opinion or support.
Means 'united', 'in solid support'. Often used for teams or groups.
Describing a geometric solid, a 3D object.
The standard term for a three-dimensional solid in geometry.
The Japanese word 固い (katai) means 'hard' or 'stiff', not 'solid' in most senses. Using it for a 'solid plan' or 'solid person' would be unnatural. Use the specific equivalents provided for each meaning.
a hard plan (unnatural)
このパンは固い。
This bread is hard.
This desk is solid and seems like it will last a long time.
Means 'solid', 'firm', 'steady'. Very common for describing construction, handshakes, arguments, etc.
This house has a solid construction, doesn't it?
Formal/literary term for 'solid', 'firm', 'strong'. Often used for defenses, structures.
It was a solid fortress.
Specifically a 'solid line' as opposed to a dashed or dotted line.
Please park inside the solid line.
Describes a solid color with no pattern. 'Solid blue' = 無地の青.
I'm looking for a solid red T-shirt.
Used before time words to mean 'a full/solid' amount of time. E.g., まるまる1時間 (a solid hour).
It took a solid day.
Means 'continuous', 'consecutive'. Can be used for solid blocks of time or unbroken stretches.
It was a solid three-hour meeting.
He is a solid person.
Means 'solid', 'steady', 'sound'. Often used for people, businesses, plans.
Let's make a solid plan.
A noun meaning 'a reliable/solid person'. Often used in casual praise.
She's a solid person, isn't she?
Eat a solid breakfast.
Means 'fulfilling', 'substantial'. Good for 'solid experience' or 'solid content'.
It was a solid day.
Means 'splendid', 'fine', 'solid'. Can be used for a solid achievement or performance.
That's a solid result.
The team was solid in their aim for the championship.
Means 'unanimously'. Used in formal voting contexts.
The proposal was passed with solid support.
A cube is a type of solid.