Pronunciation: (bum'pur-tu-bum'pur), [key]
1. marked by a long line of cars moving slowly or with many stops and starts, one behind the other: bumper-to-bumper traffic.
2. Informal.following one another in profusion: bumper-to-bumper worries.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.