noun
artificial fly; fly lure
A fishing lure made to imitate insects or small fish, used in fly fishing.
See also: フライ
渓流で毛針を使ってヤマメを釣った。
I caught a yamame trout in the mountain stream using a fly lure.
彼は自分で毛針を巻いている。
He ties his own flies.
Rarely used kanji form with 鈎 (hook).
フライ is a more general loanword for 'fly' in fishing, while 毛針 specifically refers to the traditional Japanese artificial fly made with feathers and thread.
Compound of 毛 (ke, 'hair, feather') and 針 (hari, 'hook, needle'), referring to a hook dressed with feathers or fur. The reading けばり is a standard rendaku form.