Underpin

Unˊder-pin′

,

Verb.

T.

[

imp. & p. p.

Underpinned

;

p. pr. & vb. n.

Underpinning

.]

1.

To lay stones, masonry, etc., under, as the sills of a building, on which it is to rest.

2.

To support by some solid foundation; to place something underneath for support.

Underpin

UNDERPIN'

, v.t.

1.

To lay stones under the sills of a building, on which it is to rest.

2.

To support by some solid foundation; or to place something underneath for support.

underpin

English

Verb

underpin ‎(third-person singular simple present underpins, present participle underpinning, simple past and past participle underpinned)

(transitive) To support from below with props or masonry.
You should underpin the mine roof to prevent further collapse.
(transitive, figuratively) To give support to; to corroborate.
Public confidence in politicians must underpin our democracy.
- 2016 October 24, Owen Gibson, “Is the unthinkable happening – are people finally switching the football off?”, in The Guardian, London:
  Since Rupert Murdoch famously bet the farm on Premier League football to rescue Sky TV in 1991, it has been the catnip that has underpinned subscriber loyalty and, even in a far more complicated media landscape, is seen as so vital as to be worth almost any price.