Jean François Fernel (Latinized as Ioannes Fernelius; 1497 – 26 April 1558)[2][3] was a French physician who introduced the term "physiology" to describe the study of the body's function.

Fernel suggested that taste buds are sensitive to fat, an idea which research in the early 21st century proved to be correct.

[5][6] He was born in Montdidier and, after receiving his early education at Clermont,[7] he entered the College of Sainte-Barbe, Paris.

[2] Catherine de' Medici, wife of King Henry II of France, sought his advice regarding their difficulty in conceiving a child.

[10] His works on mathematical and astronomical subjects also include Monalosphaerium, sive astrolabii genus, generalis horarii structura et usus (1526), and De proportionibus (1528).