(computing) A testing arrangement in which a beta test version of software is distributed to a small group of testers.

The display of text on a television or video screen, usually a transcription of the audio portion of a program as it occurs (either verbatim or in edited form), most frequently used by the deaf and language learners. Closed captions are encoded invisibly, and displayed by a decoder.

plural of closed book

(topology) A set whose complement is open.

(algebra, field theory, of a field) Which contains as an element every root of every nonconstant univariate polynomial definable over it (i.e., over said field).

(uncountable, chess) A chess opening characterized by the moves 1.d4 d5, in which both White and Black move their queen's pawn to the fourth rank with their first move.

(mathematics) A form (expression) that does not use limits, implicitly or explicitly. / (mathematics) A differential form whose exterior derivative is zero.

The state or quality of being closed-minded.

(education) Referring to an examination in which external resources such as glossaries, study notes, and calculators are prohibited.

plural of closed compound