William Louis Abbott (23 February 1860 – 2 April 1936) was an American medical doctor, explorer, ornithologist and field naturalist.

[1] He obtained a Bachelor of Arts at the University of Pennsylvania in 1881 before studying medicine there, graduating in 1884 and subsequently doing postgraduate studies in England, obtaining licentiates from the Royal College of Physicians and Royal College of Surgeons.

In 1886, he received a substantial inheritance, ceased the formal practice of medicine, and devoted himself to exploration and collecting.

[2][3] In 1923, Abbott retired from active fieldwork but continued to provide funding on several occasions to the United States National Museum for other collecting expeditions.

He died at his farm on the Elk River in Maryland of heart disease after a long illness, leaving his books, papers and 20% of his estate to the Smithsonian Institution.