The term 'calendar line' refers to a WEEK-long timeline that is used to organize events and tasks. It is typically divided into seven days, with each day representing a different day of the WEEK. The crossword solution for this term is 'WEEK, ' which is an acronym for 'Work, Eat, Exercise, and Keep.' This acronym is used to remind people to prioritize their activities and ensure that they are taking care of themselves.