Specific database terminology. Somepossible definitions:

# A schema is the set of objects (tables, views, indexes, etc) belonging to an account. It is often used as another way to refer to an Oracle account. The CREATE SCHEMA statement lets one specify (in a single SQL statement) all data and privilege definitions for a new schema. One can also add definitions to the schema later using DDL statements.
www.orafaq.com/glossary/faqgloss.htm

# a description of the structure and rules a document must satisfy for an XML document type. Includes the formal declaration of the elements that make up a document.
members.optusnet.com.au/~webindexing/Webbook2Ed/glossary.htm

# A description of the data represented within a database. The format of the description varies but includes a table layout for a relational database or an entity- relationship diagram.
www.inproteomics.com/nwglosrs.html

# A conceptual model of the structure of a database that defines the data contents and relationships. A database definition language specification is an implementation of a particular schema.
www.ittia.com/dbstar/manual/UG_Gloss.htm

# An information model implemented in a database. A schema may be a logical schema, which will define, for example, tables, columns, and constraints, but which may not include any optimization. It may be a physical schema that includes optimization, for example, table clustering.
www.georgetown.edu/uis/ia/dw/GLOSSARY0816.html