noun
circular knitting needle
A knitting needle with a flexible cable connecting two needle tips, used for knitting in the round.
セーターを編むときは、輪針を使うと便利です。
When knitting a sweater, it's convenient to use circular needles.
棒針 refers to straight knitting needles, while 輪針 is a circular needle with a cable.
Compound of 輪 (わ, 'ring, circle') and 針 (はり, 'needle'), referring to the circular shape of the needle.