"Whomped up" is a colloquial phrase usually used to indicate something that has been hastily put together. Some synonyms for "whomped up" include "slapped together," "thrown together," "cobbled together," "put together in haste," and "hastily assembled." These words are often used to describe something that has been done quickly without much thought or planning involved. Other synonyms that can be used to describe quickly arranged things include "improvised," "ad-hoc," "impromptu," "makeshift," and "off-the-cuff." These synonyms help to convey the idea that something has been created quickly and without much forethought, which can often lead to less than optimal results.