delete https://{youraccountname}.api-us1.com/api/3/tasktypeOutcomeRels/
Delete an existing task type - outcome relation
If the deal task type has existing deal tasks, the request will be rejected with a HTTP response code 409. Before this deal task type can be deleted, all deal tasks under this deal task type must be either moved to another deal task type or deleted. To move deal tasks under the deal task type to another deal task type, please see Move deal tasks to another deal task type.