Definition from Wiktionary, the free dictionary
From Latin quadrātūra.
quadrature (plural quadratures)
- the process of making something square; squaring
- (mathematics) 
- the process of constructing a square having the same area as a given plane figure
- computing that area (or finding definite integral) symbolically or numerically
- finding indefinite integral. Solving differential equation by quadratures (reduction to quadratures) — finding solution as integrals of elementary functions ()
- (astronomy) a situation in which three celestial bodies form a right-angled triangle, the observer being located at the right angle
- When the Moon is in quadrature, it appears in the sky as a half-moon.
- (physics) the condition in which the phase angle between two alternating quantities is 90°
- (art) A painting painted on a wooden panel
Derived terms 
- Plural form of quadratura