from The American Heritage® Dictionary of the English Language, 5th Edition.
- noun A slight convexity or swelling, as in the shaft of a column, intended to compensate for the illusion of concavity resulting from straight sides.
from The Century Dictionary.
- noun In architecture, the swelling or outward curve of tho profile of tho shaft of a column.
- noun In pathology, constrictive or tonic spasm, as cramp, lockjaw, etc. See
tetanus. Also entasia.
from the GNU version of the Collaborative International Dictionary of English.
- noun (Arch.) A slight convex swelling of the shaft of a column.
- noun (Med.) Same as
from Wiktionary, Creative Commons Attribution/Share-Alike License.
- noun architecture A slight
convex curvatureintroduced into the shaft of a columnfor aesthetic reasons, or to compensate for the illusion of concavity.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- noun a slight convexity in the shaft of a column; compensates for the illusion of concavity that viewers experience when the sides are perfectly straight
from The American Heritage® Dictionary of the English Language, 4th Edition
from Wiktionary, Creative Commons Attribution/Share-Alike License
The ancient Greeks used a technique known as entasis which incorporates a slight convexity in the columns of the Parthenon to compensate for the illusion of concavity created by parallel lines.
"I was reading a guide book which explained that the bulging of the columns 'base - known as entasis - is to counteract the well-known visual illusion that if you don't bulge them out in the middle, they appear waisted in the middle.
Beard is rather dismissive of their optical sophistication, shown in the curvature of the stylobate and in the entasis of the columns — the slight outward swelling of a column designed to counter the optical illusion of concavity, were the columns 'sides to be perfectly straight.
With regard to the enlargement made at the middle of columns, which among the Greeks is called [Greek: entasis], at the end of the book a figure and calculation will be subjoined, showing how an agreeable and appropriate effect may be produced by it.
The entasis as given by Fra Giocondo in the edition of 1511. 2.
And they are an illustration of what was a marked characteristic of all classic architecture, which shows a slight curvature or entasis in its long lines.
This peculiarity is a convexity, or _entasis_, as it is called, on the inner faces.
These provide the slight entasis to the outline which is found in so many spires, as it is in classic columns, and is designed to correct the appearance of hollowness which would occur in so long a straight line.
The exaggeration in the entasis of the archaic column disappears, its tapering was diminished, its height increased, and the overhang of the capitals reduced, till in the Theseion (465 B. C.) and the Parthenon (450-438 B. C.) we reach the final inimitable type.
The Legacy of Greece Essays By: Gilbert Murray, W. R. Inge, J. Burnet, Sir T. L. Heath, D'arcy W. Thompson, Charles Singer, R. W. Livingston, A. Toynbee, A. E. Zimmern, Percy Gardner, Sir Reginald Blomfield
The entasis from the temple of Mars Ultor in Rome compared with