Definition & Meaning of "entasis"

What is "entasis"?

Entasis refers to a slight curve or swelling that is built into columns or pillars in architecture. This design choice is used to create an optical illusion, making the columns appear straight and more visually pleasing. Without entasis, straight columns may seem to bulge or appear less stable due to the way light and shadow interact with them. By adding this gentle curve, architects enhance the elegance and strength of the structure, which can be seen in many classical buildings, especially those from ancient Greece and Rome.