Methylene Blue, methylthionine chloride or 3,7-bis(dimethylamino)phenothiazin-5-ium chloride is a chemical compound used as a dye and medication for Gram's stain, Wright stain[?], and the treatment of metoxyhemoglobinemia.
... is a compound
of "mat" (me) and "stha" (standing, staying at) and
means "they are in me".
"-aham" (I) in the second line is nominative. na caaham =
"...and not ...