The definition of irk is to annoy.(verb)
See irk in Webster's New World College Dictionary
Origin: ME irken, to loathe, be weary of, akin to northern & N Midland adj. irk, yrk, weary, troubled < ? ON yrkja, to work
See irk in American Heritage Dictionary 4
transitive verb irked, irk·ing, irks
Origin: Middle English irken, to weary
Origin: , possibly from Old Norse yrkja, to work, make verses, harangue; see werg- in Indo-European roots.
Learn more about irk