plane1
  
  n.
  - a flat surface on which a straight line joining any two points would wholly lie. ▸an imaginary flat surface through or joining material objects. ▸a flat surface producing lift by the action of air or water over and under it. 
- a level of existence or thought:![]()  the spiritual plane. 
adj.
  - completely level or flat.
- relating to only two-dimensional surfaces or magnitudes:![]()  plane and solid geometry. 
v.
  - (of a bird or an airborne object) soar without moving the wings; glide.
- (of a boat, surfboard, etc.) skim over the surface of water as a result of lift produced hydrodynamically.
Etymology
  C17: from L. planum ‘flat surface’, neut. of planus ‘plain’ (adj.).
 
  
    
plane3
  
  n.
 a tool consisting of a block with a projecting steel blade, used to smooth a wooden surface by paring shavings from it.
v.
 smooth with a plane.
Etymology
  ME: from a var. of obs. Fr. plaine ‘planing instrument’, from late L. plana, from L. planare ‘make level’.
 
  
    
plane4
  
  n.
 a tall spreading tree of the northern hemisphere, with maple-like leaves and bark which peels in uneven patches. 
[Genus 
Platanus.]
Etymology
  ME: from OFr., from L. platanus, from Gk platanos, from platus ‘broad’.