noun
fine-point brush; detail brush
A very fine brush used for painting delicate lines, especially in traditional Japanese painting, doll-making, and detailed craftwork.
面相筆で人形の目を描く。
I paint the doll's eyes with a fine-point brush.
Compound of 面相 (mensō, 'face, facial features') and 筆 (fude, 'brush'), referring to a brush fine enough to paint facial details.