1. A remarkable or impressive achievement that is claimed or supposed to have happened, but not yet proven or verified
The alleged feat of climbing Mount Everest without oxygen equipment was later disputed by mountaineers.
A façanha alegada de escalar o Monte Everest sem equipamento de oxigênio foi posteriormente contestada por montanhistas.
2. A purported accomplishment or exploit that is said to have occurred but lacks confirmation or evidence
Scientists questioned the alleged feat of creating cold fusion in the laboratory.
Cientistas questionaram a façanha alegada de criar fusão fria em laboratório.