Play word 糸爪 糸爪 いとづめ groove in a shamisen player's fingernail caused by the friction of the string of the instrument
Play word 糸道 糸道 いとみち groove in a shamisen player's fingernail caused by the friction of the string of the instrument
Play word 練り糸 練り糸 ねりいと glossy silk thread (made from raw silk treated in a solution to dissolve the sericin)