Loss of open-mindedness is a phenomenon that can be described in various ways. One synonymous term to depict it is 'intellectual rigidity', which refers to a situation where an individual becomes unwilling to consider, accept or tolerate ideas or opinions that differ from their own. Another expression is 'narrow-mindedness', which highlights a lack of tolerance for diverse perspectives. 'Close-mindedness' is an additional phrase that signifies an inability or resistance to embrace new or unconventional concepts. 'Dogmatism' is also a term that suits the description since it implies an extreme adherence to a particular belief or practice, without regard for other views. In summary, there are multiple words that can be used interchangeably with 'loss of open-mindedness' dependent on context and suitability.