Origins
The word 'compute' means to calculate, to determine by mathematical means, or to reckon a quantity. It entered English in the 1630s from Latin 'computāre' (to count, to sum up, to reckon together), a compound of the prefix 'com-' (together, wholly) and the verb 'putāre.' The path through French — Old French 'computer' or 'conter' — also produced the English word 'count,' making 'compute' and 'count' doublets: two English words derived from the same Latin ancestor through different routes.
The Latin verb 'putāre' had two distinct but etymologically connected meanings. In its original, concrete sense, it meant 'to prune, to cut clean, to trim' — specifically to prune trees and vines. In its extended, abstract sense, it meant 'to reckon, to calculate, to think, to consider, to settle accounts.' The connection between pruning and reckoning lies in the ancient practice of keeping tallies by cutting notches in wooden sticks. A tally stick with notches was a record of quantities — debts, inventories, measurements — and the act of 'cutting' (putāre) was simultaneously the act of 'reckoning.' The English Exchequer (royal treasury) used tally sticks for accounting well into the nineteenth century.
The deeper root of 'putāre' is PIE *pewH- (to cut, to strike, to stamp). From the 'cutting' sense of 'putāre,' English also acquired 'amputate' (from 'amputāre,' to cut around, to prune away). From the 'reckoning/thinking' sense, the family expanded enormously: 'dispute' (from 'disputāre,' to reckon separately, to argue), 'reputation' (from 'reputātiō,' a reckoning up, an estimation), 'deputy' (from 'dēputāre,' to consider as, to assign), 'impute' (from 'imputāre,' to reckon to one's account, to attribute), and 'repute' (from 'reputāre,' to think over).
Word Formation
The word 'computer' — now among the most important nouns in any language — was formed from 'compute' with the agent suffix '-er' and originally referred to a person who computes. From the seventeenth century through the mid-twentieth century, a 'computer' was a human being whose occupation was performing mathematical calculations. The term was used in astronomy (computing planetary positions), navigation (computing courses), and later in military contexts (computing ballistic trajectories and code-breaking calculations).
During World War II, teams of women — many of them mathematicians — were employed as 'computers' by the U.S. Army and Navy, performing the vast calculations needed for artillery tables, cryptanalysis, and logistics. At the University of Pennsylvania, six of these women computers — Kay McNulty, Betty Jennings, Betty Snyder, Marlyn Wescoff, Fran Bilas, and Ruth Lichterman — were selected to program ENIAC (Electronic Numerical Integrator and Computer), one of the first general-purpose electronic computers, completed in 1945. The machine inherited the job title of the women who had previously done its work by hand.
The related word 'count' arrived in English earlier, in the fourteenth century, from Anglo-French 'counter' (to count, to tell), from Latin 'computāre.' The phonological reduction from 'computāre' to 'conter/counter' is a normal development in French, where unstressed internal syllables were often lost. The existence of both 'compute' and 'count' in English — a more learned Latinate form and a more colloquial French-derived form — is a typical example of the lexical layering created by the Norman Conquest.
French Influence
From 'count' came 'account' (from Old French 'aconter,' to reckon up), 'recount' (to count again; also to tell, to narrate — because 'conter' in French meant both 'to count' and 'to tell a story,' preserving the ancient connection between enumeration and narration), 'discount' (to count off, to deduct), and 'counter' (a table for counting, later any flat surface for transactions).
The semantic journey of the 'putāre' family — from pruning vines, to cutting notches in tally sticks, to reckoning quantities, to abstract thinking and argumentation, to electronic computation — is one of the most remarkable chains of metaphorical extension in etymological history. It demonstrates how a concrete physical action (cutting) could, over millennia, become the foundation for humanity's most abstract intellectual activities. When a modern computer 'computes,' it is, at the deepest etymological level, 'cutting notches together' — an echo of Stone Age accounting that now powers artificial intelligence.