Definition of "dale"

And we will all the pleasures prove / That hills and valleys, dales and fields, / Woods, or steepy mountain yields

c. 1587, Christopher Marlowe, The Passionate Shepherd to His Love

Five miles meandering with a mazy motion, / Through wood and dale the sacred river ran, / Then reached the caverns measureless to man, / And sank in tumult to a lifeless ocean: [...]

1797, S[amuel] T[aylor] Coleridge, “Kubla Khan: Or A Vision in a Dream”, in Christabel: Kubla Khan, a Vision: The Pains of Sleep, London: […] John Murray, […], by William Bulmer and Co. […], published 1816, page 57

The country about Nuncombe Putney is perhaps as pretty as any in England. It is beyond the river Teign, between that and Dartmoor, and is so lovely in all its variations of rivers, rivulets, broken ground, hills and dales, old broken, battered, time-worn timber, green knolls, rich pastures, and heathy common, that the wonder is that English lovers of scenery know so little of it.

1869 May, Anthony Trollope, “The Clock House at Nuncombe Putney”, in He Knew He Was Right, volume I, London: Strahan and Company, […], page 113

Over hill, over dale / As we hit the dusty trail, / And those caissons go rolling along.

1908, Edmund Louis Gruber, The Caissons Go Rolling Along

The pump-dale scupper is that to which the dale leads, that conveys the water from the pumps to the side on the lower deck of large ships.

1853, John Fincham, An Outline of Ship Building in Four Parts‎, page 40