Editing Entasis (section)

===In calligraphy===
In [[calligraphy]] and [[typography]] entasis refers to the use of a concave curve to thin — rather than widen — the waist of a stroke<ref>{{Cite book|author=Folsom, Rose|url=http://worldcat.org/oclc/22859467|title=The calligraphers’ dictionary|date=1990|publisher=Thames and Hudson|isbn=0-500-01489-2|oclc=22859467}}</ref> or character. In calligraphy this is achieved either through  a slight heightening of the pen or brush angle and/or by an increase in the speed of the stroke as it goes into a straight. Visually it is reminiscent of the structure of a bone and a stroke is seen as stronger for it. Entasis in a stroke is intended to counter the illusion a stroke with perfectly straight sides has of bulging slightly.