miasma
mi·as·ma  (mī-ăz′mə, mē-)
n. pl. mi·as·mas or mi·as·ma·ta (-mə-tə)
1. A noxious atmosphere or influence: "The family affection, the family expectations, seemed to permeate the atmosphere ... like a coiling miasma" (Louis Auchincloss).
2.
a. A poisonous atmosphere formerly thought to rise from swamps and putrid matter and cause disease.
b. A thick vaporous atmosphere or emanation: wreathed in a miasma of cigarette smoke.

Basically means in this context, a highly unpleasant smell. Something that's pungent. Classic word choice, been a while since I last read that one!

I sourced a Jap GNR (immaculate) for a mate and it had the Taito metal badge proudly affixed to the side of the head box. I actually liked it - good historical reference