backlog

nouns

an accumulation of jobs not done or materials not processed that are yet to be dealt with (especially unfilled customer orders for products or services)
backlog
is a type of (narrower)
several things grouped together or considered as a whole
accumulation, aggregation, assemblage, collection
the large log at the back of a hearth fire
backlog
is a type of (narrower)
wood used for fuel
"they collected and cut their own firewood"
firewood
something kept back or saved for future use or a special purpose
backlog, reserve, stockpile

verbs

accumulate and create a backlog
backlog
is a type of (narrower)
collect or gather
"Journals are accumulating in my office"; "The work keeps piling up"
accumulate, amass, conglomerate, cumulate, gather, pile up