Yes, Elasticsearch can also be considered as the No-SQL database. Like MySQL, SQL Server, elasticsearch is also a database engine and database management system. But elasticsearch does not support relational DBMS. If you consider the high-level, elasticsearch also allows you to store information and to retrieve data based on queries which provide results which proves Elasticsearch can act as the database. Among the ACID properties of the database, Elasticsearch only fulfills atomicity, consistent and durable so you can safely call Elasticsearch as a database.