The term 'Number Five Iron' is a golf club, specifically the fifth iron in a set of clubs. The crossword solutions for this term are 'MASHIE' (6 letters) and 'FYSNLJ' (6 letters). MASHIE is an old-fashioned term for a type of golf club, which is a slightly shorter and more lofted iron than a modern 5-iron. FYSNLJ is an acronym for 'For Your Shortest Next Longest Journey', which is a phrase used to describe the purpose of a 5-iron club.