Akt prawa miejscowego w znaczeniu UK; Przepisy wewnętrzne, np. wewnątrzzakładowe prawo pracy - w znaczeniu US.
There are multiple definitions - click on the translation that matches your context.
(UK) a law made by a local government that only relates to its particular region
A new bylaw has been introduced to ban fishing for salmon and sea trout along a stretch of Cumbria coastline.
(US) a rule made by a company or organisation that its members must obey
The manager is appointed according to the corporation's bylaws.