Definitions
1.AdjectiveOf a land, suitable or allowable for constructing a building on.
2.AdjectiveOf a building or other thing, capable of being constructed.
3.AdjectiveThat can be constructed in a plane using only a pair of compasses and a straightedge.
4.AdjectiveSuch that the line segment joining it to the origin can be constructed using only a pair of compasses and a straightedge.
5.AdjectiveAdmitting description as a finite union of locally closed (with respect to the Zariski topology) sets.