Geometry Symbols

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

This is a list of the most common Geometry symbols:

SymbolDefinitionExample
\(\triangle\) triangle \(\triangle ABC \)
\(\angle\) angle \(\angle ABC = 60^\circ\)
\(\measuredangle\) measured angle \(\angle ABC = 60^\circ\)
\(\sphericalangle\) spherical angle \(\angle AOC = 60^\circ\)
\(^\circ\) degree 1 circle \(= 360^\circ\)
' arcminute \(1^\circ = 60^\prime\)
" arcsecond \(1'=60^{\prime\prime}\)
\(rad\) radiant, \(1 \;rad = 180^\circ /\pi \;\) and \(\;1^\circ = \pi / 180 \;rads\) \(360^\circ = 2\pi\; rad\) or about \(57.2958^\circ\)
\(grad\) gradian, four hundredth (1/400) of a full circle \( 360^\circ = 400\; grad\)
\(\overleftrightarrow {AB}\) infinite line distance  
\(\overline {AB}\) line segment from A to B  
\(\overrightarrow {AB}\) start line at point A  
\(\overset{\frown} {AB}\) arc from A to B  
\(|A-B|\) 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 \(\overline {AB} \perp \overline {XY} \)
\(\sim\) similarity \(\triangle ABC \sim \triangle XYZ\)
\(\cong\) congruent, equivalent in size and shape \(\triangle ABC \cong \triangle XYZ\)
\(\therefore\) therefore \( a=b\; \therefore\; b=a \)
\(\pi\) \(\pi = 3.141592654... \) \(C = \pi \cdot d = 2 \cdot \pi \cdot r\)