1. An accomplishment or remarkable achievement that has not been officially recorded, verified, or formally acknowledged in written records or official documentation
The athlete's undocumented feat of running the marathon in record time was witnessed by spectators but never officially registered.
O feito não documentado do atleta de correr a maratona em tempo recorde foi testemunhado por espectadores, mas nunca foi oficialmente registrado.
2. An act or achievement that exists in folklore, oral tradition, or anecdotal evidence rather than in verifiable, written records
Local legends speak of an undocumented feat of strength performed by a village elder generations ago.
As lendas locais falam de um feito não documentado de força realizado por um ancião da aldeia gerações atrás.