With the launch of Dynamics 365 at the end of 2016, Microsoft blurred the lines between its CRM and ERP offering:
Classic Dynamics CRM modules became “Dynamics 365 for Sales” or “Dynamics 365 for Customer Service”, while Dynamics AX was referred to as “Dynamics 365 for Operations”
With the July 2017 Update of Dynamics 365, Microsoft clarified its license plans names, and generally what was previously in Dynamics CRM is now included in Dynamics 365 Customer Engagement.
Similarly, what was part of AX is now referred to as Dynamics 365 Unified Operations.
To summarize the current Dynamics 365 offering (excluding the Business Edition):