slack

Compared meaning: soft, loose, and lacking firmness or tension (adjective).

比较义项：柔软、不挺括、缺乏张力或硬度（形容词）。

• limp

  Limp describes something, often a body part, plant, or handshake, that has lost its usual firmness or energy, suggesting weakness or tiredness rather than mere looseness.

  limp形容某物（常指身体部位、植物或握手）失去了原有的挺度或活力，显得虚弱无力，而不只是松弛。

  Her handshake was so limp it barely registered as a greeting.

  她的握手软弱无力，几乎让人感觉不到那是在打招呼。

• slack 本词

  Slack describes a rope, wire, or line that is not pulled tight, so it has extra give; it focuses on tension, not overall softness, and rarely describes a body part.

  slack形容绳索、电线或缆线没有被拉紧，还有松余的部分；它强调的是张力，而不是整体的柔软，也很少用来形容身体部位。

  He noticed some slack in the rope and pulled it tight.

  他注意到绳子有些松弛，就把它拉紧了。

• floppy

  Floppy describes something soft and flexible that hangs, swings, or flops loosely, often at one end, like ears, hats, or hair; the word is lighter and often affectionate.

  floppy形容某物柔软而有弹性，会松垮地垂下、摆动或耷拉，常指一端固定的东西（如耳朵、帽子、头发），语气更轻松，有时带点可爱的意味。

  The puppy had big, floppy ears that flapped when it ran.

  这只小狗有一对松垮的大耳朵，跑起来时会一甩一甩的。

Limp, slack, and floppy describe something soft or not firm. Limp suggests weakness, like a limp handshake. Slack means not tight, like a loose rope. Floppy means soft and hanging loosely. Limp can also mean walking unevenly, and slack can mean lazy; not compared here.

这三个词在“柔软、不挺括”这一义项上意思相近，但语气和典型搭配不同：limp常带虚弱、无力的意味，slack强调张力不够、有松余，floppy则强调松垮下垂、语气较轻松。这里不比较limp作动词“瘸着走”的用法，也不比较slack表示“懈怠、业务清淡”的用法。