Take action, especially following a time of indecision or delay. For example, It's time this administration got off the dime and came up with a viable budget. This expression originated in the 1920s in dance-halls as an imperative for dancers to get moving. By 1926 it had been extended to other activities.
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.