polynuclear aromatic hydrocarbons
1. premature nodal contraction 2. prenatal care
abbreviation 1. perceived noise decibel
1. a combining form meaning “breath, respiration,” used in the formation of compound words that denote a kind of breathing or condition of the respiratory system, as specified by the initial element: dyspnea; hyperpnea. -pnea suff. Breath; respiration: dyspnea.
pneum- pref. Variant of pneumo-.