a chameleonlike person who is unusually ubiquitous (from Woody Allen film "Zelig")
(verb) hesitate or be reluctant to do something that one thinks may be wrong OR (noun) a feeling of doubt or hesitation with regard to the morality or propriety of a course of action
an indirect tax charged on the sale of a particular good and paid by the merchant/producer
promiscuous and unprincipled in sexual matters