三维
sān wéi · HSK 7
three-dimensional
🧊 三维 = 三 (three) + 维 (dimension) → three-dimensional, 3D
三 means three; 维 means dimension or to tie together. A 三维 model has three dimensions: length, width, height. Compare 二维 (2D, two-dimensional).
三 — three horizontal strokes 一 + 一 + 一
三 is a pictographic numeral: three stacked horizontal lines representing the number three, parallel to 一 (one) and 二 (two). The form has been stable since oracle bone script. It carries no phonetic component; the meaning 'three' is direct and visual.