a beginning from which an enterprise is launched; "he uses other people's ideas as a springboard for his own"; "reality provides the jumping-off point for his illusions"; "the point of departure of international comparison cannot be an institution but must be the function it carries out"
an estimation that is too low; an estimate that is less than the true or actual value
make too low an estimate of; "he underestimated the work that went into the renovation"; "Don't underestimate the danger of such a raft trip on this river"