evennight

The story

1. Proto-West Germanic · derived from*ebnanaht“equinox”
2. Old English · learned borrowing fromefnniht
3. English todayevennight

Learned borrowing from Old English efnniht, from Proto-West Germanic *ebnanaht (“equinox”), equivalent to even- + night. Cognate with Old Frisian evennacht, ivinnacht, Old Norse jafnnætti. Compare also Dutch nachtevening (“equinox”).