smellfungus
A faultfinder, complainer, grumbler.
archaic
But this want of a softening medium, and consequently, of aerial perspective, is not the defect of the Rhine scenery in particular, but of river views in general. And then it is so rich in equivalents—so strong in picture; a true Smellfungus would exclaim, “Yes; but the pictures are all alike.”
Where it comes from
From Smelfungus, name of a hypercritical traveller in A Sentimental Journey Through France and Italy, a satirical characterization of Tobias Smollett and his Travels Through France and Italy (1766). Apparently from smell + fungus.
Adapted from the Wiktionary entry smellfungus (CC BY-SA 4.0).