Once every half-hour, every 30 minutes.

At intervals of a half-hour, every 30 minutes.

(US) A permit to be out of class during school hours. / (by extension, informal) An agreement to temporarily or conditionally relax monogamy in a relationship.

(idiomatic, of a person, plan, theory, etc.) Shrewd but flawed by overthinking or excessive complexity, with a resulting tendency to be unreliable or unsuccessful.

(psychology) A cognitive bias in which judgment of somebody's character is influenced by an overall impression of him or her.

(of coffee) consisting of equal parts decaf and regular coffee.

Coffee of this kind, or a serving of it.

A piece of land which is "halfway" an island; a byland; peninsula. / An area of land occupying part or half of an island.

Alternative form of halfgod

(Ireland) A council-sponsored campsite for members of the Travelling Community.