The term TIME UNIT can be broken down into six crossword solutions: ISSUE (5 letters), SECOND (6 letters), EON (3 letters), HOUR (4 letters), YEAR (4 letters), and ARTICLE (7 letters). An ISSUE is a problem or topic that needs to be addressed, and is usually measured in seconds, hours, or years. An EON is an extremely long period of TIME, often used to describe geological eras. A SECOND is a UNIT of TIME equal to one sixtieth of a minute. An HOUR is a UNIT of TIME equal to sixty minutes. A year is a UNIT of TIME equal to 365 days. An ARTICLE is a written piece on a particular subject, which can be measured in any UNIT of TIME.