Endocrine, from the Greek endon, within, and krinein, to separate.

Friedrich Henle first recognised the presence of ductless glands in 1841, but "endocrine" was not used to describe these structures until the French physiologist Gustave-Edouard Laguesse coined the term in 1893.

Laguesse also named the islets of Langerhans, the pancreatic endocrine tissue that is the source of insulin and glucagon, among other hormones. They were so-called in honor of Paul Langerhans, the German who first described islet anatomy in 1869 (but did not suggest any functions).

The word hormone was coined in 1905 by British physiologist Ernest Starling (from the Greek word for “excite", hormao.)

Gustave-Edouard Laguesse (1861-1927) www.chru-lille.fr