Meaning of BUG in English
An unintentional error in software or hardware . For software bugs the application may stop altogether or produce unexpected results. There are various stories of where the term originated the most famous from about 50 years ago credited to a moth that was squashed between components of an ancient computer.
English glossary of Internet and PC terminology. Английский глоссарий Интернет и ПК терминологии. 2012