To drop (something); to let something fall or lose it — a transitive verb, dialectical variant similar in meaning to 'otosu'.
道で財布を落っことしてしまった。誰か届けてくれてるかな。
I dropped my wallet on the street. I wonder if someone has turned it in.
携帯を落っことさんように気をつけてや。
Be careful not to drop your phone.
仕事の書類を落っことしたら大変やから、机の上に置いとき。
It would be a disaster if you lost the work documents, so leave them on the desk.