extrapolate
ik-STRAP-uh-laytverbMeaning to use known facts or trends to predict what lies beyond them
Memory hook EXTRA-polate: draw the line EXTRA far. Lin’s sunflower grew a foot each week, so she draws the line extra far, past what she has measured: “By August it will beat the fence!” To predict that way is to extrapolate.
From three weeks of growth, Lin extrapolated that her sunflower would top the fence by August.
In context The town had grown by about a hundred people a year for a decade, so planners extrapolated from that trend to estimate how many classrooms they would need in ten years.
Similar project, extend, predict, infer
Formed from extra (beyond) and the ending of interpolate, “to fill in between known points.”