say it: it-UR-puh-lay-shuhn
interpolation is a noun meaning "a message (spoken or written) that is introduced or inserted". It carries 3 recorded senses.
(mathematics) calculation of the value of a function between the values already known
mathematics
the action of interjecting or interposing an action or remark that interrupts
Forms marked · are formed by the regular rule rather than recorded in the source data. English keeps a few hundred irregulars and the rest follow the pattern, so the rule is right far more often than not — but it is a rule, and the mark says so.
Definitions, synonyms and semantic relations for interpolation come from Princeton University’s WordNet. The pronunciation comes from the CMU Pronouncing Dictionary. Commonness is measured against a corpus of everyday English. Full sources and licences.