This is the 563rd most frequent Slovenian word.
dneva
"Dneva" means "of the day" or "day's" in English.
As used here, 'dneva' refers to the part of the day when sunlight is present, showing its genitive singular usage for indicating 'of the day (in terms of daylight)'
Imel sem samo dvanajst ur dneva, preden je padel mrak.
I had only twelve hours of daylight before dusk fell.
In this sentence, 'dneva' is used in the genitive case to specify a temporal boundary: 'end of the day'.
Do konca dneva moramo dokončati to nalogo.
We must complete this task by the end of the day.
Here, 'dneva' is in the genitive singular form referring to a specific part of the day, 'middle of the day'.