verb (used with object), un·der·pinned, un·der·pin·ning.

to prop up or support from below; strengthen, as by reinforcing a foundation.
to replace or strengthen the foundation of (a building or the like).
to furnish a foundation for; corroborate: The author's conclusions are underpinned by references to experimental findings.

Nearby words

  1. underpants,
  2. underpart,
  3. underpass,
  4. underpay,
  5. underperform,
  6. underpinning,
  7. underpinnings,
  8. underpitch vault,
  9. underplant,
  10. underplay

Origin of underpin

First recorded in 1515–25; under- + pin

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for underpin

British Dictionary definitions for underpin


verb -pins, -pinning or -pinned (tr)

to support from beneath, esp by a prop, while avoiding damaging or weakening the superstructureto underpin a wall
to give corroboration, strength, or support to
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for underpin



1520s (figurative); 1530s (literal), from under + pin (v.). Related: Underpinned; underpinning.

Online Etymology Dictionary, © 2010 Douglas Harper