noun
(loosely) A collection of (usually) organized information in a regular structure, usually but not necessarily in a machine-readable format accessible by a computer.
(computing) A set of tables and other objects (queries, reports, forms) in the form of a structured data set.
(computing, loosely, metonymic) A software program (application) for storing, retrieving and manipulating such a structured data set.
(computing, loosely, metonymic) A combination of such data sets and the programs for using them.
verb
(transitive) To enter (data) into a database.