Sometimes the sinker can be replaced by a cage- or keg-like feeder which contains and releases groundbait to better attract fish.
In stock market terminology, bottom fishing can mean buying the cheapest investments (in terms of valuation ratios) available.
The term can be derogatory as it can imply a lack of attention to the quality of the investments selected.
In stock trading, bottom fishing can also describe the practice of driving the price of a security lower in order to trigger stop-loss orders, which will then commonly drive a security's price even lower, at which point the person or entity responsible for the triggering will then buy up those shares.
As part of this phenomenon, a security's price will then often rise again quickly above the stop-loss order mark.