Backup and Fall back

Backup noun - A crowded mass (as of cars) that impedes or blocks movement.

Fall back and backup are semantically related. In some cases you can replace term "Fall back" with "Backup", this nouns are similar.

Nearby Word: backing

Fall back verb - To move back or away (as from something difficult, dangerous, or disagreeable).

Backup and fall back are semantically related. Sometimes you can use "Backup" instead a noun "Fall back".