The present participle of fixate; the ongoing action of focusing obsessively on something.
From fixate plus -ing gerund/participle suffix, creating a verbal noun or continuous action form.
Neuroscience shows that people with anxiety disorders have brains that literally get 'stuck' on fixating—their attention circuits don't disengage properly, which is why telling someone to 'just stop fixating' is like telling them to stop breathing.
Complete word intelligence in one call. Free tier — 50 lookups/day.