Sentence:  Moreover, the Supreme Court has held that the President must obey outstanding executive orders, even when <WSD>bottomed</WSD> on the Constitution, until they are revoked. 
Meaning of the word marked with <WSD> tags:  To establish firmly; to found or justify "on" or "upon" something; to set on a firm footing; to set or rest "on" or "upon" something which provides support or authority.