reliable /ɹɪˈlaɪəbl̩/adjective 2noun 1forms 3 adjective2 •working well or doing what was promised each time, so that people can trust itthe best means, and the most reliable pledge, of a higher object — 1800 •Such that either a sent packet will reach its destination, even if it requires retransmission, or the sender will be told that it didn't. noun1 •Something or someone reliable or dependable formsreliables · more reliable · most reliable