underpinning
noun /ˌʌndəˈpɪnɪŋ/
/ˌʌndərˈpɪnɪŋ/
[countable, uncountable]- (formal) something that supports or forms the basis of an argument, a claim, etc.
- the theoretical underpinnings of the study
- (specialist) the act of supporting a wall and making it stronger by putting metal, concrete (= a hard building material), etc. under it; the metal, concrete, etc. that supports the wall
- The only way to save the building is through extensive underpinning.