Arm and Hammer (actually, "Arm & Hammer") is a registered trademark of Church and Dwight, an American manufacturer of household products. The logo of this brand, is, unsurprisingly, a muscular arm holding a hammer. The brand was originally associated only with baking soda; beginning in the 1970s the company began to expand the brand to other products which included baking soda as an ingredient, including a line of toothpastes and deodorants. It now includes items that contain no baking soda whatever such as liquid laundry detergent, but all or most are associated with the idea of cleaning and cleanliness. The Arm & Hammer brand is one of the longest-running and most recognized U.S. trademarks. It is not true that the brand has its origin in the name of former Occidental Petroleum chairman Armand Hammer; it in fact far predates him, although in the 1980s Hammer acquired a considerable amount of Church and Dwight stock, apparently finding humor in the coincidence. At the time of his death, he seems to have been taking his investment seriously, as he was serving on Church and Dwight's Board of directors.

The Arm and Hammer was also the symbol of the Socialist Labor Party of America, which in the 1890s was led by, among others, Julius Hammer, the father of industrialist and art collector Armand Hammer. This party's symbol was a muscular male arm tightly clutching a hammer in its fist; in 1898 Julius named his newborn son after his favorite political logo. (As a young man Armand was himself associated with American leftist parties and the USSR.) The story that he told about being named for a hero in an Alexandre Dumas fils novel was apocryphal.