This is the 193rd most frequent Czech word.
dlouho
"Long" or "for a long time."
Here, "dlouho" is used to describe the duration of the waiting period, indicating that it lasted a significant amount of time.
Čekal jsem dlouho na autobus.
I waited for the bus for a long time.
"Dlouho" here indicates a relatively short time duration since the last occurrence of the event, showing its flexibility in expressing time spans.
Není dlouho od té doby, co jsem tě naposledy viděl.
It hasn't been long since I last saw you.
In this sentence, "dlouho" is part of the question asking about the duration of the activity, effectively making it a query about time commitment.