Plane

piano

(of a surface: flat or level.)

aereo

(airplane)

aeroplano

(airplane)

pialla

(a tool)

piallatrice

(a tool)

pialletto

(a tool)

piano

(level or flat surface)

piano

(geometry: flat surface extending infinitely in all directions)

piano

(level of existence)

platano

(deciduous tree)

piallare

(to smooth with a plane)

planare

(to move in a way that lifts the bow of a boat out of the water)

planare

(to glide)