Imapassibly is an adverb that describes someone or something that is impossible to affect or move emotionally. Synonyms for this word include unemotionally, stoically, unresponsive, expressionless, detached, and impassive. Other alternatives include insensible, apathetic, unfeeling, dispassionate, indifferent, and phlegmatic. These synonyms may be used interchangeably depending on the context in which the word is being used. For example, an individual may show an impassively expression when experiencing a great loss, while others may show no response at all. Using synonyms for "impassibly" in writing or speech can help expand one's vocabulary and make communication more interesting and engaging.