As you know some single words may be written in various forms, e.g.like nosy and nosey or Noruz may be written Norooz, Narooz, Nawru, Nauruz, Nawroz, Noruz, Nohrooz, Novruz, Nauroz, Navroz.
In Persian dokme/tokme , zoqal/z̤oqal, belit/beliṭ ,...
In Linguistics we say: Noruoz is ?????
of Noruz.
Such words have same pronunciation or a very similar pronunciation. They have same origin but when are enter to another language they are written differently.
A lot of such words can be found in this forum thread: Multiple Spellings of the Same Word.
Please suggest a single word for indicated area, e.g. Polygraph
(Source)