constructible

Short definition from Wiktionary

Adjective

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