A physical thing that typifies an abstract thing; an embodiment or personalization(noun)
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Use "externalization" in a sentence
"What so often results might be described as a subjectivization of those norms, that is, their externalization into the medium of expression itself, and a simultaneous inner transformation of their content and significance."
"Naturally, some kind of externalization would inevitably follow."
"Those afflicted by this syndrome rationalize their cold-heartedness to themselves by "externalization" (finding outside enemies to blame for their failures) and "splitting" (attempting to hide something in their background that they are ashamed of)."