• WordNet 3.6
    • n entasis a slight convexity in the shaft of a column; compensates for the illusion of concavity that viewers experience when the sides are perfectly straight
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Webster's Revised Unabridged Dictionary
    • Entasis (Arch) A slight convex swelling of the shaft of a column.
    • Entasis (Med) Same as Entasia.
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Century Dictionary and Cyclopedia
    • n entasis In architecture, the swelling or outward curve of tho profile of tho shaft of a column. The entasis exists in perfection in the finest examples of Greek Doric, in which the swelling is greatest a little below the middle point of the shaft, but never so great as to interfere with the steady diminution of the shaft from the base upward. The entasis is designed both to counteract the optical illusion which would cause the profiles of the shafts to appear curved inward if they were bounded by straight lines, and to give the effect of life and elasticity to the column in its function of supporting superimposed weight.
    • n entasis In pathology, constrictive or tonic spasm, as cramp, lockjaw, etc. See tetanus. Also entasia.
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Chambers's Twentieth Century Dictionary
    • n Entasis en′ta-sis (archit.) the swelling outline of the shaft of a column—also Entā′sia: constrictive or tonic spasm
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Webster's Revised Unabridged Dictionary
NL., from Gr. a stretching; fr. ; in + to extend
Chambers's Twentieth Century Dictionary
Gr.,—en, in, teinein, to stretch.


In literature:

This is called the entasis of the spire, and belongs to the study of optics in architecture.
"Our Homeland Churches and How to Study Them" by Sidney Heath
The entasis is almost invariably introduced in the spires of English churches.
"Encyclopaedia Britannica, 11th Edition, Volume 9, Slice 6" by Various