Undisturbed by passion or caprice; calm; tranquil; serene; not passionate or giddy; composed; staid; as, a sedate soul, mind, or temper.

cause to be calm or quiet as by administering a sedative to; "The patient must be sedated before the operation"

dignified and somber in manner or character and committed to keeping promises; "a grave God-fearing man"; "a quiet sedate nature"; "as sober as a judge"; "a solemn promise"; "the judge was solemn as he pronounced sentence"

characterized by dignity and propriety