Shirk is first attested in the 17th century, perhaps from German Schurke ('scoundrel, rogue'), of uncertain ultimate origin. The quoted older sense, "scoundrel, rogue," supplies the immediate semantic anchor for shirk. The formation is best read as borrowed: the word shirk carries its older form-history into a compact English lexical shape. In present English it is used as a verb, "to avoid or neglect a duty or responsibility". English derivatives include shirker and shirking. The result is a verb whose etymology preserves both the older form and the later English specialization.