The term `yiic` stands for Yii Framework Console, which is a CLI to run Yii Console application commands.
Yii Console applications are mainly used to perform offline work needed by an online Web application, such as code generation, search index compiling, email sending, etc. Yii provides a framework for writing console applications in an object-oriented way. It allows a console application to access the resources (e.g. DB connections) that are used by an online Web application.