1. When there is a sub for a teacher and that sub gets sick, the next sub is the dubsub
2. enough subway stuff to fill two sandwiches but is only in one.
"That dubsub we had wasnt any good. i want our sub back"
"No way i want the real teacher back!"
"Thats a lot of meat"
"Yeah i guess its a dubsub, that lady packed it on"