A “bumper crop” is a result of extraordinary abundance.
You can have a bumper business, bumper crowds, or bumper crops.
This ancient use of bumper comes from a drinking goblet called a “bumper,” which was filled to the brim when used for toasts.
While quaffing a bumper of ale, drinkers touched, or bumped these goblets against one another during a festive or celebratory occasion such as an excellent harvest, business growth, or full houses at theatrical performances.
