extrapolate

UK: /ɪkˈstræp.ə.leɪt/ | US: /ɪkˈstræp.ə.leɪt/

Definition

  1. vt. to estimate or infer (something unknown) by extending or projecting known information

  2. vt. to extend the application of (a method or conclusion) to an unknown situation by assuming existing trends will continue

Structure
extra <beyond>pol <adjust/align>ate <verb suffix>
Etymology

The word "extrapolate" combines Latin-derived morphemes:

  • "Extra" (from Latin extra, meaning "beyond") suggests extension outside known limits.
  • "Pol" (from Latin polire, "to polish" or polari, "to adjust") implies refining or aligning data.
  • The suffix "-ate" forms verbs indicating action.
    Originally used in mathematics (19th century), it described projecting trends beyond observed data. The logic mirrors "interpolate" (filling gaps within data), but "extrapolate" extends beyond existing boundaries.
Examples

  1. Scientists extrapolate future climate patterns from current data.

  2. The report extrapolates market growth based on past trends.

  3. You can't reliably extrapolate a global trend from a single case study.

  4. The model extrapolates population changes over the next century.

  5. Historians cautiously extrapolate cultural shifts from fragmentary evidence.