n.
Pronunciation: ' si-z ə -j ē
Function: noun
Inflected Form: plural -gies
Etymology: Late Latin syzygia conjunction, from Greek, from syzygos yoked together, from syn- + zygon yoke ― more at YOKE
Date: circa 1847
: the nearly straight-line configuration of three celestial bodies (as the sun, moon, and earth during a solar or lunar eclipse) in a gravitational system