/.timername <i> <d> <c>

name - Whatever you care to name the timer, avoid using numbers for names as some of those are reserved. There is no space between the name and the word timer.

<i> - The number of intervals, for this case you only need 1.
<d> - The delay time or time to wait between intervals.
<c> - The command to execute on each interval.

As an example to your question:

/.timerCloseIt 1 10 dialog -x listmaster

This starts a timer named CloseIt that, after a single interval of 10 seconds will close the dialog and stop.