“Plane” can be short for “airplane.”
It can also be used in terms of an intellectual or moral level.
A plane is a wood-working device that removes the bumps and ridges from wood, and “to plane” is to use that device.
It can refer to a flat or level surface, such as a table top.
In geometry, a “plane” is a flat surface, a two-dimensional figure.
A “plain” is a flat geographic area.
Think: The rain in Spain falls mainly on the plain (geography).
Each of those words contains the “ai” of “plain,” so if the covered wagons are crossing the wide-open prairie (another “ai”), the synonym is “plain.”
“Plain” can also mean “not decorated” or “not fancy,” maybe even “boring.” For those used to mountains or forested areas, the treeless plains can seem very plain.
Another meaning of “plain” is “obvious,” “evident.”
- The plain truth was that the man from the plains was innocent.
- (“plain” = simple, unadorned; “plains” = prairies, geographical area)
- On a moral plane, the resolution to his guilt or innocence was difficult to determine.
- (“moral plane” = level of morality)
- It is plain to me that no agreement will ever be reached.
- (“plain” = evident, obvious)
- If the person holding out would just take a plane and fly away, I think the rest of us could agree.
- (“plane” = airplane)