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.
I write New Year's cards with a brush.
This brush is very easy to write with.
She wrote her New Year's cards with a calligraphy brush.
We use a calligraphy brush in calligraphy class.