early 15c., "an exchange, act of exchanging reciprocally," from Old French entrechange, from entrechangier (see interchange (v.)). Meaning "alternate succession" is from 1550s. In reference to a type of road junction, 1944.
1650s, "to arrange in grades," from grade (n.). Meaning "to reduce (a road, etc.) to a level or degree of inclination" is from 1835. Meaning "assign a letter mark to" is from 1931. Related: Graded; grading.
"a herd, especially of cattle," Old English draf "beasts driven in a body; road along which cattle are driven," originally "act of driving," from drifan "to drive" (see drive (v.)).