William Hunter was born in East Kilbride, Lanarkshire on 23 May 1718 and was the older brother of John Hunter. In 1736, after five years spent at the University of Glasgow with the intention of joining the church, Hunter left to take up a medical apprenticeship with William Cullen and the two even agreed to go into partnership together once Hunter had completed his training. Hunter attended the anatomy lectures of Monro primus in Edinburgh in 1739 and the following year headed to London where he learnt midwifery from William Smellie and was introduced to James Douglas, whose anatomy assistant he became. Hunter joined the Douglas household in 1741, tutored his son, and remained there for several years.
Hunter gave his first paper to the Royal Society in June 1743 on the subject of articular cartilages, derived from his work with Douglas. He travelled to Paris later in the year where he attended prestigious anatomy and surgery lectures. On his return to London in summer 1744 he began building his own surgical and midwifery practice. Hunter launched his first anatomy course in October 1746, taking advantage of a recent split between the surgeons and the barbers. He became a member of the Company of Surgeons in 1747, temporary man-midwife to the Middlesex Hospital in 1748, and was appointed man-midwife to the new British Lying-in Hospital in 1749, a post he held until 1759. He had taken a brief trip to Leiden in 1748 and on his return his brother John joined him in London and the two brothers left the Douglas household in 1749 and moved to a house in Covent Garden with lecturing facilities. He gave lectures here until 1760 and also in Litchfield Street from 1768 until his death in 1783.
Hunter returned to Scotland in the summer of 1750 during which time he became a guild brother of the city of Edinburgh and received the degree of MD from Glasgow University. In 1752 he was elected one of the masters of anatomy at Surgeons' Hall. In 1754 he became a member of the Society of London Physicians and in 1756 chose to leave the Company of Surgeons in favour of becoming a licentiate of the Royal College of Physicians. In 1762 Hunter safely delivered Queen Charlotte of a son and was appointed physician-extraordinary to the queen. In 1767 he was elected a fellow of the Royal Society and the following year was appointed professor of anatomy to the Royal Academy.
In 1767 Hunter famously opened his specially designed anatomy school on Great Windmill Street and moved in the following year and remained there for the rest of his life. Hunter made a great many contributions to anatomy and midwifery in particular, including work on the relationship between the maternal and foetal blood systems, which was not without its controversies in terms of who was really responsible for the discoveries. Hunter was known for his experimental approach and favoured practical demonstrations. He published a number of papers with one of his most significant works being The anatomy of the gravid uterus (1774), but much of his work went unpublished with many significant aspects now found amongst former students' lecture notes. He was also known for his vast collections of anatomical specimens, books, coins, and shells.
Hunter died at his home at Great Windmill Street on 30 March 1783.