A unit of time is a measure of a certain amount of time, such as a SECOND, MINUTE, HOUR, DAY, MONTH, year, ERA, EON, or ISSUE. The crossword solutions for the term unit of time are SECOND (6 letters), MINUTE (6 letters), YEAR (4 letters), EON (3 letters), DAY (3 letters), ERA (3 letters), HOUR (4 letters), MONTH (5 letters), and MSEC (4 letters). A SECOND is the smallest unit of time, while an EON is the longest unit of time. A MINUTE is 60 seconds, an HOUR is 60 minutes, a DAY is 24 hours, a MONTH is usually 30 days, a year is 365 days, an ERA is a long period of time, and a millisecond is one thousandth of a SECOND.