The term scientist refers to someone who performs scientific study in order to increase knowledge in a particular field of interest.
There was no genuine ancient equivalent of a contemporary scientist in classical antiquity. Instead, philosophers engaged in the philosophical study of nature, which was known as natural philosophy at the time and was a forerunner to modern natural science today. After been created by theologian, philosopher, and historian of science William Whewell in 1833, it was not until the 19th century that the word scientist became widely accepted.
Nowadays, many scientists have graduate degrees in a specific field of research and work in a variety of industries, government agencies, and non-profit organisations.