deltoid
/ˈdɛɫtɔɪd/noun
High School
1
The deltoid muscle, a triangular muscle on the human shoulder.
2
The deltoid ligament, a triangular ligament on the human ankle.
3
A kite (quadrilateral having two pairs of edges of equal length, the edges of each pair touching each other at one end).
4
A deltoid curve (hypocycloid with three cusps).