This is the 4425th most frequent Polish word.
jasna
"Jasna" in English means "bright" or "clear."
Here, 'jasna' (clear) is used to denote clarity or obviousness of a subject.
To jest jasna sprawa.
This is a clear matter.
'Jasna' (bright) is used to describe positivity or enlightenment in a metaphorical sense.
Spójrz na jasną stronę życia.
Look at the bright side of life.
In this context, 'jasna' describes the intensity of light in terms of luminance.