From Middle English yestreen, alteration of yestereven (“last night, yesterday evening”), from Old English ġiestranǣfen (“yesterday evening”), equivalent to yester- + e'en (“evening”). Cognate with West Frisian justerjûn (“yestreen; last night”).
yestreen (plural yestreens)
- (chiefly archaic, poetic or Scotland) The night before.
- see list in yestereve