Something curvilinear is made of curved lines, or has a curved shape, rather than straight ones. Architects use it for roofs and walls that sweep and bend. Designers use it for patterns. Mathematicians use it for grids that follow curves instead of a simple square. It is a formal, school-and-studio word. In everyday talk people just say curved. Though actually, curved can mean one simple bend, while curvilinear often means the whole design is built from curves — not a box with one rounded corner, but lines that keep curving. The opposite idea is straight-line, like a grid of boxes.

曲線形的、曲線的