Umpteen is a slang term used to describe an unspecified large number. It is often used in place of the term 'a jillion, ' which is also used to describe an unspecified large number. UMPTEEN is derived from the word 'UMPTEEN, ' which is defined as 'an indefinite number greater than ten or twelve.' Therefore, the crossword solutions for the term 'a jillion' can be summarized as a slang term used to describe an unspecified large number, usually greater than ten or twelve.