William McAdam (c. 1725 – October 1, 1779) was a Scottish-American merchant and businessman who served as the president of the Saint Andrew's Society of the State of New York.
[2] He was a direct descendant of Gilbert McAdam, "a zealous covenantor" who was killed by the Royalists in 1685 while "attending a prayer-meeting at Kirkmichael in Ayrshire.
By 1766, he had a warehouse on Smith Street, near the New Dutch Church, where he sold "Iron-bound Butts & Puncheons, genuine Batavia Arrack in Bottles, Frontinjack, Priniack & Madeira, etc.
"[2] During the height of his career, he brought his nephew John Loudon McAdam (son of brother James) over to New York to work as a merchant and prize agent in his counting house.
His nephew later returned to Scotland and became a well-known civil engineer and road-builder who invented the process known as "macadamisation", an economical method of constructing roads.