"miniaturized processor capable of serving as the central processing unit of a computer," by 1970, from micro- + processor.
Entries linking to microprocessor
micro-
word-forming element meaning "small in size or extent, microscopic; magnifying;" in science indicating a unit one millionth of the unit it is prefixed to; from Latinized form of mikros, Attic form of Greek smikros "small, little, petty, trivial, slight," perhaps from PIE *smika, from root *smik- "small" (source also of Old High German smahi "littleness"), but Beekes thinks it a Pre-Greek word.
processor n.
"person or machine which performs a process," 1909, agent noun in Latin form from process (v.). Data processor is from 1957; word processor is from 1973; food processor in the kitchen appliance sense also is from 1973.