'Entasis' definitions:

Definition of 'entasis'

(from WordNet)
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

Definition of 'Entasis'

From: GCIDE
  • Entasis \En"ta*sis\, n. [NL., from Gr. ? a stretching; fr. ?; ? in + ? to extend.]
  • 1. (Arch.) A slight convex swelling of the shaft of a column. [1913 Webster]
  • 2. (Med.) Same as Entasia. [1913 Webster]