murrain
Used as an intensifier: extremely, very.
figuratively, obsolete
It is a murrion crafty drab, and froward to be pleaſed.
Where it comes from
The noun is derived from Late Middle English morein, morine, moreyn (“(widespread) death; widespread sickness, plague; fatal disease; carnage; carrion”), from Anglo-Norman morine, mourine, moreyn (“death; widespread sickness, plague; carrion; cattle disease”), Middle French morine, and Old French morine, mourine, murine (“widespread sickness, plague; animal which has died from a disease”), from Late Latin morina (“plague”), probably from Latin morior (“to die; to decay, wither”). The adjective and adverb are derived from the noun. Cognates * Italian morìa (“plague”) * Latin morticīnus (“that has died naturally, dead; (relational) carrion”) (Medieval Latin morticinium) * Occitan moria (“death; plague”) * Old French morie (“death”) mourie (“flesh of animals that have died of disease”) (Middle French murie) * Portuguese morrinha (“cattle plague”) * Spanish morriña (“cattle plague”)
Adapted from the Wiktionary entry murrain (CC BY-SA 4.0).