Definition of underprop in US English:

underprop

verb

[with object]archaic
  • Support, especially with a prop.

    • ‘A bearing is provided for underpropping the shaft extension of the free end of the printing roller.’
    post, rod, pillar, column, support, foundation, piling
    View synonyms

Pronunciation

underprop

/ˌəndərˈprɑp//ˌəndərˈpräp/