/
trəˈdʒɛkt(ə)ri, 
ˈtradʒɪkt(ə)ri/
n.
 (pl. trajectories)
  - the path described by a projectile flying or an object moving under the action of given forces.
 - Geometry  a curve or surface cutting a family of curves or surfaces at a constant angle.
 
Etymology
C17: from mod. L. trajectoria (fem.), from L. traject-, traicere ‘throw across’.