The word "stem" is easy to remember. It's just four letters, one syllable. The word is a familiar one in the American English vocabulary as it can have several meanings. When you use it as an acronym, STEM takes on a whole new meaning that is greater and more complex than the rest, yet it's still easy to remember. When today's doctors, scientists, engineers and mathematicians were just kids, there was no simple acronym to refer to the difficult and challenging areas of science, technology, engineering and math.