Lethologica is a state of mind when one cannot remember a particular word or phrase. It can be frustrating when you are trying to communicate something, and the word just won't come to mind. However, there are a few synonyms that can be used for lethologica which are tip-of-the-tongue phenomenon, blackout, and aphasia. Tip-of-the-tongue phenomenon is when you know the word, but you struggle to recall it. Blackout is the complete inability to remember something. Aphasia is a more severe form of lethologica, where the person has difficulty speaking, reading and writing. These synonyms all describe different levels of forgetfulness, but they help to convey the same idea, a moment when the right word just won't come to mind.