solid

Compared meaning: firm and hard to press or break (adjective).

比较义项：坚固、坚硬（形容词）。

• solid 本词

  Solid describes something firm and dense all the way through, not hollow or shaky, emphasizing sturdy overall structure rather than surface texture.

  solid 形容物体从里到外都坚实、不空心、不摇晃，强调整体结构牢固，而不是表面质地。

  The old wooden staircase felt solid, so we didn't worry about it collapsing.

  这座旧木楼梯感觉很坚固，所以我们不担心它会塌。

• hard

  Hard describes a surface that resists pressure, scratching or cutting, focusing on texture rather than the object's overall sturdiness.

  hard 形容表面能抵抗压力、不易被划伤或切开，侧重的是质地本身，而不是物体整体是否牢固。

  The diamond is so hard that it can scratch almost any other material.

  钻石非常坚硬，几乎能划伤其他所有材料。

Both describe something firm and strong, but focus differently. Solid describes something dense and sturdy all the way through, not hollow. Hard describes a surface that resists pressure or scratching. Hard's other meaning, difficult, as in a hard problem, is not compared here.

这两个词都可以形容物体质地坚实、不易变形，但侧重不同：solid 强调物体内部密实、结构牢固、不空心；hard 强调表面坚硬、不易被按压或划伤。这里不比较 hard 的另一个常见义项“困难的”（如 a hard problem）。