Robert Nesbit Howard originally had the surname Hormadze, but changed it to Howard in 1889. He qualified as a member of the Royal College of Surgeons (MRCS, England), a licentiate of the Royal College of Physicians (LRCP, Edinburgh), and a licentiate of the Society of Apothecaries of London (LSA) in 1880. He subsequently became a member of the British Medical Association. In January 1883 he was licensed to practice in the Cape Colony and was employed as medical officer to the Cape Copper Company, which was mining at Okiep, just north of Springbok. By 1893 he had settled at Springbokfontein (now Springbok) and was also district surgeon of Namaqualand. By 1895 he was living in Port Nolloth, but still held the same positions. At this time he was a member of the Cape of Good Hope Branch of the British Medical Association. By 1898 he had joined the (second) South African Medical Association. He moved to Okiep (then still spelled O'okiep) around 1901 and remained medical officer (later chief medical officer) of the Cape Copper Company to the end of 1916. In 1904 he was appointed as Justice of the Peace in Namaqualand.
Howard's interest in science was manifested in several ways. He donated Bushman arrowheads and pieces of pottery to the Albany Museum, Grahamstown, in 1894. More important were his zoological donations to the South African Museum during 1898 and 1899. These included some 20 mammals, several snakes, and 20 scorpions. As a result he was named as one of only nine "correspondents" of the museum, who received its publications free of charge. In 1910, while residing at O'Kiep, he presented a collection of snakes, frogs, spiders and scorpions to the Albany Museum. The donation was particularly welcome as the museum had very little material from Namaqualand at the time.
Meanwhile Howard had been elected a Fellow of the Royal Meteorological Society and in 1899 and 1900 manned a second order meteorological station at Port Nolloth for the Cape of Good Hope Meteorological Committee. He was elected a member of the South African Philosophical Society in 1889, and was still a member of its successor, the Royal Society of South Africa, in 1917. By 1903 he had also joined the South African Association for the Advancement of Science.
During 1916 Howard was incapacitated for several months by cardiac trouble. After his retirement at the end of that year he settled in Cape Town, where he served as a captain in the South African Medical Corps at Alexandra Military Hospital in Maitland from the middle of 1917 to March 1918. This was followed by a year as locum at Herschel, until he commenced practicing at Jamestown in March 1919. He died later that year, leaving a widow and adult children.