Relating to, used for, or involving calculation or mathematical computation.
From Latin calculatorius, derived from calculator (one who calculates). The suffix -ory indicates a relationship or function.
Calculatory is a rare English word now, but it shows the productive power of Latin suffixes: -tor (one who does), -tory (relating to doing)—the same pattern gives us 'investigator' and 'investigatory,' 'administrator' and 'administrative.'
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