We can also delete properties from objects like this:

delete ourDog.bark;

The delete operator removes a property from an object.

delete expression where expression should evaluate to a property reference, e.g.:

delete object.property
delete object['property']

object The name of an object, or an expression evaluating to an object.

property The property to delete.

Throws in strict mode if the property is an own non-configurable property (returns false in non-strict). Returns true in all other cases.

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