go·ni·om·e·ter 
(g
ō′n
ē-
ŏm
ĭ-t
ər)
n.1. An optical instrument for measuring crystal angles, as between crystal faces.
2. A radio receiver and directional antenna used as a system to determine the angular direction of incoming radio signals.
[Greek gōniā, angle; see genu-1 in the Appendix of Indo-European roots + -METER.]
go′ni·o·metric (-nē-ə-mĕtrĭk), go′ni·o·metri·cal adj.
go′ni·ome·try n.