(music) A genre of rave music typified by a very fast tempo and a bright, cheerful sound, often coupled with solo vocals and sentimental lyrics.

plural of happy ending

(Australia) Used to express displeasure at someone else's incompetence.

plural of happy-clappy

plural of happy medium

(idiomatic) A balanced position between two opposite extremes.

(colloquial, transitive) To wish (someone) a happy birthday.

Said or written to a person who is celebrating his or her birthday in order to convey the good wishes of the speaker or writer (literally, "may you have a happy birthday")

A McDonald's brand boxed kid's meal.

A fast food restaurant packaged kid's meal, usually a ready-to-eat hot meal. A meal combo for a child, which is stereotypically boxed and including a toy; typically comprising a main dish, side dish (usually french fries), drink (frequently a juice box), and dessert (frequently a cookie).