I got a compilation of definitions of data warehouse glossary by the experts some time ago.

Business Intelligence - The capability to perform in-depth analysis and possibly data mining, of detailed business data, providing real and significant information to business users.  Business Intelligence usually makes use of tools designed to easily access data warehouse data.

Data warehouse - A collection of integrated, subject-oriented databases designed to support the decision support system (DSS) function, where each unit of data is relevant to some moment in time.  The data warehouse contains atomic data and lightly summarized data.