plaguey

Plagues have, well, "plagued" humanity for centuries. One sense of the word plague, referring to a deadly fever transmitted from rodents to humans by way of infected fleas, was all too familiar to English speakers in the late 16th century. That's when the word plaguey first appeared on the scene as an adjective describing something relating, literally or figuratively, to a plague. The fact that "plaguey" developed its "annoying" meaning by the end of that same century suggests just how familiar, and troublesome, the disease was in those days. "Plaguey" is also sometimes used as an adverb meaning "irritatingly," as in "it is plaguey cold." (The form "plaguily" is occasionally seen as well, with the same meaning.)