Crossword puzzles flex one very specific piece of cognition--the ability to find words, which is also known as fluency. Fluency is a type of process based in the speech and language centers of the brain. So doing crosswords might help you get better at word finding, but that's the sum total of their positive benefits to your brain.
misnomer. n. 1. an incorrect or unsuitable name or term for a person or thing. 2. the act of referring to a person by the wrong name.
Antonyms are two words that have opposite meanings. Synonyms are words that have the same or nearly the same meaning. Homonyms are words that are pronounced the same, and are sometimes spelled the same, but have different meanings. 1  Dictionary.  Dictionary.