A bad speller is someone who has difficulty spelling words correctly. The term can be used to describe someone who is a poor speller in general, or someone who is particularly bad at spelling certain words. Two crossword solutions for the term 'bad speller' are 'SORCERER' (8 letters) and 'cacographer' (11 letters). A SORCERER is someone who practices magic, and the term can also be used to describe someone who is very skilled at something. Cacographer is a more specific term, referring to someone who is an especially poor speller.