The term 'Revolution Period' refers to a period of time in which a major change or transformation occurs. The two crossword solutions for this term are 'YEAR' (4 letters) and 'ONEYEAR' (7 letters). The word 'YEAR' is a unit of time that is typically divided into 12 months, while the word 'ONEYEAR' is a period of time that lasts for one year. Both words refer to a period of time that can be used to describe a revolution period.