‘We dug down to the underlying rock.’;
lying over or upon something else
basic or fundamental
‘Points and straight lines are underlying elements of geometry.’;
Lying over or upon something; as, overlying rocks.
‘Many nursery rhymes have an underlying meaning.’;
placed on or over something else;
‘an overlying image’;
(finance) The entity from whose performance a derivative derives its value.
Lying under or beneath; as, the underlying strata of a locality.
Fundamental; basic; as, underlying principles; underlying causes.
Implicit; not immediately obvious; requiring careful scrutiny to discover; as, the underlying sarcasm in her seemingly innocuous remark..
in the nature of something though not readily apparent;
‘shortcomings inherent in our approach’; ‘an underlying meaning’;
located beneath or below
being or involving basic facts or principles;
‘the fundamental laws of the universe’; ‘a fundamental incompatibility between them’; ‘these rudimentary truths’; ‘underlying principles’;
In finance, the underlying of a derivative is an asset, basket of assets, index, or even another derivative, such that the cash flows of the (former) derivative depend on the value of this underlying. There must be an independent way to observe this value to avoid conflicts of interest.