The word 罪恶滔天 is formed by combining the compound 罪恶, meaning "crime and evil", with the phrase 滔天, meaning "reaching the sky" or "flooding the heavens". Here, 滔天 acts as a hyperbolic modifier to intensively describe the scale or severity of 罪恶, resulting in a literal sense of "crimes and evils so vast they reach the sky", used to denote extreme wickedness or heinousness.