The term 'pollution portmanteau' is a combination of two words, 'smaze' and 'SMOG'. Smaze is a five-letter word that is a combination of the words 'SMOKE' and 'HAZE', and it refers to a combination of SMOKE and HAZE in the air. SMOG is a four-letter word that is a combination of the words 'SMOKE' and 'FOG', and it refers to a combination of SMOKE and FOG in the air. Together, these two words form the term 'pollution portmanteau', which is used to describe a combination of SMOKE, HAZE, and FOG in the air.