This woman has a peaceful demeanor.
Demeanor is defined as the way a person behaves.
An example of demeanor is someone being peaceful.
outward behavior; conduct; deportment
Origin of demeanorMiddle English demenure from demenen, to rule, govern oneself, behave from Old French demener, to lead from de- (L de), from + mener, to lead from Late Latin minare, to drive (cattle) from Classical Latin minari, to threaten: see menace
The way in which a person behaves; deportment. See Synonyms at behavior.
(countable and uncountable, plural demeanors)