Mary Somerville née  Fairfax (1780-1872), was a self-taught mathematician and polymath from Jedburgh in Scotland.

She is the person for whom the word scientist was invented. She studied mathematics and astronomy and was admitted as one of the first female members of the Royal Astronomical Society, together with Caroline Herschel. She was also a tutor and friend to Ada Lovelace.

Her acclaimed translation, "The Mechanisms of the Heavens", from French to English of Pierre Laplace's ground-breaking book on celestial mechanics, with her own additions, became a standard university textbook. Her book On the Connexion of the Physical Sciences became one of the best-selling science books of the nineteenth century, highlighting the underlying unity of scientific disciplines.

She campaigned for votes and education for women and said "Age has not abated my zeal for the emancipation of my sex from the unreasonable prejudice too prevalent in Great Britain against a literary and scientific education for women."

The word scientist was first used in 1834 in a review of Mary's work by William Whewell (1794-1866), Master of Trinity College Cambridge, and her personal friend. He was conscious that people working in scientific disciplines needed a more specific word than 'philosopher' to describe them: he coined 'scientist' by analogy with 'artist' and 'economist.'

When Mary Somerville died in 1872 at the age of 92, still working on her latest dissertation on the day before she died, it was written: "Whatever difficulty we might experience in the middle of the nineteenth century in choosing a king of science, there could be no question whatever as to the queen of science."