/kwod"reuh cheuhr, -choor'/ , n.
1. the act of squaring.
2. Math.
a. the act or process of finding a square equal in area to a given surface, esp. a surface bounded by a curve.
b. the act or process of finding an area or calculating an integral, esp. by numerical methods.
c. a definite integral.
3. Astron.
a. the situation of two heavenly bodies when their longitudes differ by 90°.
b. either of the two points in the orbit of a body, as the moon, midway between the syzygies.
c. (of the moon) those points or moments at which a half moon is visible.
4. Electronics. the relation between two signals having the same frequency that differ in phase by 90°.
[ 1545-55; quadratura, equiv. to quadrat ( us ) (ptp. of quadrare; see QUADRATE) + -ura -URE ]