Definify.com
Webster 1913 Edition
Pentagonal
Pen-tag′o-nal
,Adj.
[Cf. F.
pentagonal
, pentagone
, L. pentagonus
, pentagonius
, Gr. [GREEK].] Having five corners or angles.
Pentagonal dodecahedron
. See
Dodecahedron
, and Pyritohedron
.