fold line

基本解释

The figure of breakage face of toppling deformation is double fold line.
倾倒变形的破坏面是双折线型的。
A folding keyboard is set forth with a numeric keypad, and one fold line located between the edge of a standard continuous space bar and the edge of the numeric keypad.
提出了一种折叠键盘，其限定有数字键区，并且一个折叠线位于标准连续空格键的边缘和数字键区的边缘之间。
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Refers to the suture line, the provincial line, fold line and so on the intersection of a short line, in order to imply that the suture is connected, as a mark of line alignment.
指与缝合线、省线、褶线等相交的一条短线，以暗示缝线相连，作为线条对位时用的记号。