草書
そうしょ highly cursive style (of writing Chinese characters); grass style
Why it means this
草 ('grass', i.e. rough, fast) + 書 (writing) — the fully cursive 'grass script' style of calligraphy, where characters flow together (contrast 楷書, 行書).
Breakdown
Each character links to its full entry — origin story, stroke order, and readings.