1
general::
Wait idly for something to occur, as in We were just marking time until we received our instructions. This idiom alludes to the literal meaning of marching in place to the time, or beat, of music. [Early 1800s]
American Heritage Idioms
2
general::
Phrase(s): mark time
Fig. to wait; to do nothing but wait. • I’ll just mark time till things get better. • Do you expect me to just stand here and mark time?
McGrawhill's American Idioms And Phrasal Verbs