[ˌʌndəˈlʌɪ], (Verb)

Definitions:
- be a significant cause or basis of (something) even if not necessarily manifest or obvious
(e.g: the fundamental issue that underlies the conflict)

- (especially of a layer of rock or soil) lie or be situated under (something)
(e.g: limestone underlies much of the site)


Phrases:

Origin:
Old English underlicgan ‘be subject or subordinate to’ (see under-, lie)