working (adj.)

late 14c., "active, busy," present-participle adjective from work (v.). From 1630s as "engaged in physical toil or manual labor as a means of livelihood." Working class is from 1789 as a noun, 1839 as an adjective. Working-day is from late 15c.; working man is by 1816.

"action, operation," verbal noun from work (v.).