Definify.com
Webster 1913 Edition
Quincunx
Quin′cunx
,Noun.
1.
An arrangement of things by fives in a square or a rectangle, one being placed at each corner and one in the middle; especially, such an arrangement of trees repeated indefinitely, so as to form a regular group with rows running in various directions.
2.
(Astrol.)
The position of planets when distant from each other five signs, or 150°.
Hutton.
Webster 1828 Edition
Quincunx
QUIN'CUNX
,Noun.
In gardening, the quincunx order is a plantation of trees disposed in a square, consisting of five trees, one at each corner and a fifth in the middle, thus :.:; which order repeated indefinitely, forms a regular grove or wood, which viewed by an angle of the square or parallelogram, presents equal or parallel alleys.