Webster's Revised Unabridged Dictionary · 1913

Delf

Delf (delf) , noun

[Anglo-Saxon delf a delving, digging. See Delve.]

A mine; a quarry; a pit dug; a ditch. [Obsolete]
The delfts would be so flown with waters, that no gins or machines could... keep them dry. — Ray

delf , noun

Same as Delftware.