Engaged in a job or other activity, as in The contractor is hard at work on the new building, or The little boy was fascinated to see the washing machine at work. [Early 1600s]
At one's office or other place of business, as in Is it all right if I telephone you at work? [Late 1800s]
Dictionary.com presents 366 FAQs, incorporating some of the frequently asked questions from the past with newer queries.