Expression Ambiguous describes when ones gender expression by definition may be traditionally or stereotypically feminine, masculine, androgynous, neutral, etc. but does not feel as though the aforementioned labels correctly define them. Some examples may be, presenting in a typically gendered way but not necessarily feeling as such, presenting in a way that is not traditionally rooted or is not one way or the other and feels neutral or anything similar would not technically work, or even having a multitude of different expressions and not feeling the need or want to specify.
This is not the same as Gender Non-Conforming, however for some the terms may be related.
Flag
The flag was created by Scourgeface, the same person who coined the term. The stripes meanings are as follows: black for ambiguity, white for separation from definition, grey for dictionary definition, pink for feminine presentation, blue for masculine presentation, yellow for neutral and other presentations, and finally purple for androgynous presentation.