Opacity (disambiguation)

Opacity or opaque may refer to:
 * Impediments to (especially, visible) light:
 * Opacities, absorption coefficients
 * Opacity (optics), property or degree of blocking the transmission of light
 * Metaphors derived from literal optics:
 * In linguistics:
 * Opaque context, a term to describe the linguistic context of co-referential terms
 * Phonological opacity, a term in phonology
 * Semantic opacity, the opposite of semantic transparency
 * Opaque travel inventory, the market of selling unsold travel inventory at a discounted price
 * Musical works:
 * Opacities (EP)
 * Computer science:
 * Measure of obscuration of background by "painting" an image, e.g. alpha channel
 * Use of an opaque data type
 * Property attributed to data that can be interpreted only by using an external entity, e.g. magic cookie technology
 * Opaque binary blob, in network-engineering and computer-science technology, a large set of binary data (a blob) that looks like garbage to those unacquainted with its internal structure.