The word "pneumascos" cannot be accurately spelled using English spelling conventions alone. Instead, we can utilize IPA (International Phonetic Alphabet) to phonetically transcribe the word as /njuːmæskoʊz/. "Pneumascos" is not a commonly known word, and its meaning is unclear without additional context. It is important to use standard spelling and clear definitions to effectively communicate and avoid confusion amongst readers or listeners.
Pneumoperitoneum.
A practical medical dictionary. By Stedman, Thomas Lathrop. Published 1920.