As to whether or not this is an actual word is disputed by many. It is the chemical name for titin, a giant filamentous protein essential to the structure, development, and elasticity of muscle. If we're talking chemistry, the longest chemical name is 189,819 letters long.author of HOW MY BROTHER LEON BROUGHT HOME A WIFE. modifies a verb, an adjective, or another adverb. Three-letter airport codes are assigned by the Federal Aviation Administration (FAA) and the International Air Transport Association (IATA).