The feeling or state of sadness; a noun form referring to deep sorrow or grief often felt after events such as farewells or losses.
あの映画を見て深い悲しさを感じた。
I felt deep sadness watching that movie.
別れの悲しさは時間が経っても消えないことがある。
The sadness of parting sometimes doesn't disappear even with time.
日記には母の死に対する悲しさが率直に書かれていた。
The diary candidly described the sadness over his mother's death.