Medical Definition of narcissistic personality disorder. : a personality disorder characterized especially by an exaggerated sense of self-importance, persistent need for admiration, lack of empathy for others, excessive pride in achievements, and snobbish, disdainful, or patronizing attitudes.
For the purposes of sym metry, letâs now move on to the most common variant of syn- , or sym- , which also means âtogether.â A sym phony is the sounding âtogetherâ of many instruments.
synergism (sinÂ´urjizÉm), n a joint action of two drugs in such a manner that one supplements or enhances the action of the other to produce an effect greater than that which may be obtained with either one of the drugs in equivalent quantity or produce effects that could not be obtained with any safe quantity of either drug, or both.