Is there a name for a "phantom" stroke handwritten by mistake?
It is called or 笔误 or 误笔 (handwriting mistake) or more colloquially &quot;写错笔划&quot; (write a wrong stroke)
写多笔划或是写少笔划都是笔误
俗语: &quot;误将冯京作马凉&quot; 就是典型的笔误引来的误会
Although 笔误 and 误笔 are interchangeable, there's also a term 口误 (slip of the tongue). Therefore, I prefer 笔误 over 误笔