yarn

Compared meaning: a thin strand of fiber for sewing or weaving (noun).

比较义项：用于缝纫、编织或织布的细长纤维条（名词）。

• thread

  A thin strand used for sewing with a needle; fine, smooth, and typically wound on a small spool.

  指用针缝纫的细线；纤细、光滑，通常缠绕在小线轴上。

  She threaded the needle and mended the button with matching thread.

  她穿好针，用配色的线缝好了纽扣。

• yarn 本词

  A thicker, often fuzzy strand used for knitting or weaving, not for sewing with a needle.

  较粗、常带绒毛的线，用于编织或织布，而不是用针缝纫。

  She bought several balls of soft yarn to knit a sweater.

  她买了几团柔软的毛线来织一件毛衣。

Thread and yarn are both thin fiber strands, and learners often confuse them. Thread is fine and used for sewing with a needle. Yarn is thicker and used for knitting or weaving. This does not cover thread meaning a 'topic' or a screw's 'thread'.

thread 和 yarn 都指细长的纤维条，容易被中文的“线”一词混淆，但用途和粗细不同：thread 细，专门用来缝纫；yarn 较粗，用来编织或织布。这里不比较 thread 的其他意义，例如“话题的线索”或“螺纹”。