# Angle and Line Symbols

Written by Jerry Ratzlaff on . Posted in Nomenclature & Symbols for Engineering, Mathematics, and Science

## Angle and Line Symbols

This is a list of the most common angle and line symbols:

SymbolDefinitionExample
$$\triangle$$ triangle $$\triangle ABC$$
$$\angle$$ angle $$\angle ABC = 60^\circ$$
$$\measuredangle$$ measured angle $$\angle ABC \;\measuredangle \;60^\circ$$
$$\sphericalangle$$ spherical angle $$\angle ABC \;\sphericalangle\; 60^\circ$$
$$c$$ radian $$360^\circ=2\pi^c$$
$$g$$ grad $$360^\circ=400^g$$
$$\circ$$ degree $$360^\circ$$
$$\pi$$ Pi,  $$\pi = 3.141592654...$$ $$C = \pi \cdot d = 2 \cdot \pi \cdot r$$
$$\overleftrightarrow { }$$ infinite line distance $$\overleftrightarrow {AB}$$
$$\overline { }$$ line segment from A to B $$\overline {AB}$$
$$\overrightarrow { }$$ start line at point A $$\overrightarrow {AB}$$
$$\overset{\frown} { }$$ arc from A to B $$\overset{\frown} {AB}$$
$$|\;\;|$$ distance between A and B $$|A-B| = 9$$
$$\parallel$$ parallel to $$\overline {AB} \parallel \overline {XY}$$
$$\nparallel$$ not parallel to $$\overline {AB} \nparallel \overline {XY}$$
$$\perp$$ perpendicular lines $$\overline {AB} \perp \overline {XY}$$
$$\bigcirc$$ circle
$$\odot$$ center of circle $$\odot A$$