"Butter someone up" means "to flatter or be nice to someone in order to get something from them". Example: I’ve stopped answering my phone when Jenny calls me. She always butters me up with lots of compliments and then asks for a big favour.
Idiom of the day: Every cloud has a silver lining. Meaning: In every bad situation there is an element of good. Example: As the trip’s been cancelled I’ll be able to go to the match this Saturday. Every cloud has a silver lining.