Something that is in its beta stage, or being tested.

Pertaining to a product sold by merchants at a discount, because the item was returned but found not to be defective.

plural of open problem

Alternative spelling of openwork

alert and vigilant

(informal) simple and obvious; easily decided

Taking place outdoors; alfresco

Describing a reverberatory furnace used to make steel, usually in mass-produced quantities. / Designating the steel so produced.

(architecture) Having large rooms with few dividing barriers such as partitions.

(of a sandwich) Being a single slice of bread with a topping. / Having an honest and sincere expression.