__c : Custom Object or Custom Field or Custom Settings
__pc : Custom Person Account/Contact Field
__r : Custom Relationship
__b : Custom Big Objects
__e : Platform Events
__mdt : Custom Metadatype
__x : External Object
__share : Custom Object Sharing Entity
__kav : Knowledge Article Version Object
__ka : Knowledge Article Object
__History : Custom Object History Entity
__del : Deleted Custom Field
__s : Custom Address Field References
Example for Custom Address Field: