Overnight success is a term used to describe someone or something that has achieved success quickly and unexpectedly. In this crossword, the solutions for overnight success are 'METEOR' and 'FEDEX'. METEOR is a 6 letter word which refers to a sudden, bright streak of light in the night sky caused by the entry of a meteoroid into the Earth's atmosphere. FEDEX is a 5 letter word which refers to the American multinational courier delivery services company.