1) This may sometimes be just a level piece of ground.
1706 to lay out another Road in his own ground … which is all upon a Flatt, Gargrave
1755 this ridge is proposed to be fixed at the foot of a hill and there is a flat at the other end of the Bridge, Dobcross. More usually, and certainly in the early references, it refers to a division in the town fields: 1220-8 totam culturam meam apud Spitalflat, Manfield
1422 ‘up to the headland of the Flattes’, Ferrybridge
1550 a flat of wheat … vj lands of hauer, Kilvington
1556 it liethe in a flate by itself and lieth in no feld, Bulmer
1624 James Megson drove … mucke Coopes over my flat in the middle field, Elmswell. As a minor place-name element it is on record from the twelfth century. It is of Old Norse origin and has a limited distribution.