The word is a compound of the term "hiyakasu" (ひやかす), meaning "to banter", "tease" or "make fun of", and "deredere" (デレデレ), which means "lovey dovey".

A "Hiyakasudere", also known as "Teasedere" (ティーズデレ) or "Smugdere" in some Western media, refers to a character who likes to tease others and sometimes flirt with those they like.

They will act really seductive in front of other people, mainly those that attract their attention, and will tease those that get embarrassed easily by their actions and words, possibly the love interest.