extrapolation

/ɛkˌstræpəˈleɪʃən/

Other forms: extrapolations

An extrapolation is kind of like an educated guess or a hypothesis. When you make an extrapolation, you take facts and observations about a present or known situation and use them to make a prediction about what might eventually happen.

Extrapolation comes from the word extra, meaning “outside,” and a shortened form of the word interpolation. Interpolation might sound like a made-up word, but it’s not. An interpolation is an insertion between two points. So an extrapolation is an insertion outside any existing points. If you know something about Monday and Tuesday, you might be able to make an extrapolation about Wednesday.

Definitions of extrapolation

1. noun

   an inference about the future (or about some hypothetical situation) based on known facts and observations
   type of:

   illation, inference

   the reasoning involved in drawing a conclusion or making a logical judgment on the basis of circumstantial evidence and prior conclusions rather than on the basis of direct observation
2. noun

   (mathematics) calculation of the value of a function outside the range of known values
   type of:

   calculation, computation, figuring, reckoning

   problem solving that involves numbers or quantities