The act or process of making something external, visible, or manifest; the condition of being revealed to the outside.
From exteriorate + -ion (noun-forming suffix). This abstract noun describes the process of bringing internal things into external form or visibility.
This word is almost completely lost to history—it appears in maybe a handful of philosophical texts from the 1600s-1700s where thinkers struggled to describe how minds create the external world.
Complete word intelligence in one call. Free tier — 50 lookups/day.