noun
Refers to a person who habitually uses flattery, often with a negative connotation of insincerity.
彼は世辞者だから、言葉をそのまま信じてはいけない。
He's a flatterer, so you shouldn't take his words at face value.
あの世辞者には気をつけたほうがいい。
You'd better be careful around that smooth talker.
おべっか使い is a more colloquial and slightly stronger term for a flatterer or sycophant.
Compound of 世辞 (flattery) and 者 (person). The exact historical derivation is uncertain, but the word transparently means 'flattery person'.