It is common knowledge that smoking is bad for your health.
publicly known
Frequency:
60
%
The scandal was publicly known to everyone in the town.
scientifically known
Frequency:
45
%
The fact was scientifically known to be true after multiple experiments.
Idiomatic Expressions for known known
Phrase: known unknowns
Meaning: Things that are recognized as potential sources of uncertainty or risk, but the specifics are not yet clear.
Usage: The project manager created a contingency plan to address the known unknowns that could impact the timeline.