neum- 93
tire- (var. neumat-, neumato-, pneumo- ) Element prefix of gr. pneuma , breath or breath, which is used in words that relate to breathing or air or gases that are manipulated by thinning or putting them under pressure.
Unlike other cases of words that originally start with a consonant followed by another non-liquid consonant, in those with the initial pn , phonetic writing (without the p ) prevailed. However, it is possible to find words like pneumatic or pneumonia written in this way in technical or scientific books; This is not surprising if one takes into account that these are words of universal use and that in other languages ??their etymological spelling is respected. (V. in Appendix II, spelling notes on this case and others similar.)