River Lethe, also known as the River of Forgetfulness, is a popular term often used in mythology to depict the river that ran through the underworld in Ancient Greece. It was believed that drinking from the waters of this river would wipe one's memory clean. River Lethe is a term commonly used in literature, music, and poetry to describe the act of forgetting. Some synonyms for River Lethe include oblivion, amnesia, forgetfulness, and blankness. Additionally, other colloquial terms like "brain fog" or "mental block" can also apply to this concept. The use of River Lethe as a metaphor continues to be relevant in modern times, especially in discussions focused on memory and recall.