calculate

Etymology

First recorded in the 1560s,^[1][2] borrowed from Latin calculātus, past participle of Latin calculāre (“to reckon, compute”),^[1][3] from Latin calculus (“small stone used in reckoning”),^[4][3] diminutive of Latin calx (“small stone; limestone”).^[4][5] It replaced Middle English calculen (mid-14th century), from Old French calculer.^[1]

The sense “to plan, devise” is attested from the 1650s, and the American sense “to think, guess” from 1830.^[1] Compare calculus.^[1]

References

1. [1] [2] [3] [4] [5] Harper, Douglas, Online Etymology Dictionary, https://www.etymonline.com
2. [1] Random House Webster's Unabridged Dictionary, New York: Random House
3. [1] [2] Simpson, J. A.; Weiner, E. S. C., eds. (1989), The Oxford English Dictionary, 2nd ed., Oxford: Clarendon Press
4. [1] [2] The American Heritage Dictionary of the English Language, Boston: Houghton Mifflin
5. [1] Wiktionary, the free dictionary, https://en.wiktionary.org