1. Staid, sedate, settled indicate a sober and composed type of conduct. Staid indicates an ingrained seriousness and propriety that shows itself in complete decorum; a colorless kind of correctness is indicated: a staid and uninteresting family. Sedate applies to one who is noticeably quiet, composed, and sober in conduct: a sedate and dignified young man. One who is settled has become fixed, especially in a sober or determined way, in manner, judgments, or mode of life: He is young to be so settled in his ways.

Did you mean sadness?