1. The act of a person who takes, collects, or harvests items left for kerbside rubbish collection with the intention of reusing or recycling those items; applies especially where the goods are otherwise collectable or saleable;
2. The items available for collection by those who op - "Mt Lawley has good opping"
1. of, for, or pertaining to examining or collecting items left for kerbside rubbish collection "an opping trip"
From "shopping", "oportunity", "openly available"
2. "Check out the retro chairs we picked up opping on Sunday".