phlegmatic
/fleg-ˈma-tik/
adjective
resembling, consisting of, or producing the humor phlegm
having or showing a slow and stolid temperament
impassive stoic phlegmatic apathetic stolid mean unresponsive to something that might normally excite interest or emotion. impassive stresses the absence of any external sign of emotion in action or facial expression. stoic implies an apparent indifference to pleasure or especially to pain often as a matter of principle or self-discipline.