smarmy - slimy
The informal word ‘smarmy’ is used to describe somebody who insincerely tries to ingratiate themselves with others in order to impress or get something. Such people typically employ excessive flattery and politeness to achieve their aims, but that sort of behaviour is usually carried out in such a smug, over-the-top way that it can be quite obvious.
I was really put off by the smarmy salesperson. He seemed the sort of person who would say anything if he thought it would get him a sale.
I can’t stand the smarminess of politicians. Most don’t really care about helping people, they just pretend they do to secure power and influence.
The job candidate was probably nervous and just trying to make a good impression, but she came off as being smarmy and insincere.