What does "quadrate" mean?

Additional senses

1. 2.Square; even; balanced; equal; exact. [Archaic] " A quadrate, solid, wise man." Howell.
2. 3.Squared; suited; correspondent. [Archaic] " A generical description quadrate to both." Harvey. Quadrate bone (Anat.), a bone between the base of the lower jaw and the skull in most vertebrates below the mammals. In reptiles and birds it articulates the lower jaw with the skull; in mammals it is represented by the malleus or incus.
3. 4.(Geom.) A plane surface with four equal sides and four right angles; a square; hence, figuratively, anything having the outline of a square. At which command, the powers militant That stood for heaven, in mighty quadrate joined. Milton.
4. 5.(Astrol.) An aspect of the heavenly bodies in which they are distant from each other 90º, or the quarter of a circle; quartile. See the Note under Aspect, 6.
5. 6.(Anat.) The quadrate bone.
6. 7.To square; to agree; to suit; to correspond; -- followed by with. [Archaic] The objections of these speculatists of its forms do not quadrate with their theories. Burke.
7. 8.To adjust (a gun) on its carriage; also, to train (a gun) for horizontal firing.