noun
brush; writing brush; painting brush
Refers specifically to a traditional brush with a hair tip, used for calligraphy (書道) or ink painting (水墨画). Contrasts with 筆 (ふで), which can also refer to modern writing tools.
毛筆で年賀状を書く。
I write New Year's cards with a brush.
この毛筆はとても書きやすい。
This brush is very easy to write with.