(the former more correct in
), in its literal meaning from
is a fastening of any kind; for
example, the meshes of a net. (Hom. il.
.) It was applied specially to the joining together the
extremities of a piece of wood, so as to give it the shape of a bow; and
hence it came to signify anything of that shape, such as a bow, an arch, or
a wheel. (Hes. Op.
.) A potter's wheel is described, in the Anthology, as κύκλος ἁψῖδος.
The next transition of meaning
is to anything vaulted
(for example, ἡ ὑπουρανία ἁψίς,
the vault of heaven,
247 b); and in this sense it was adopted in architecture, first, for any
building or portion of a building of a circular form, or vaulted (Plin. Ep. 2.17.18
), and more especially for
the circular and vaulted end of a Basilica. (Paul. Nol. Ep.
12; Augustin, Ep.
203; Isid. Orig.
the application of the word in Christian churches, see Dict. of
S. V. APSE.