Based upon trusted and confidential computing platforms, telecommunications systems must provide guaranteed security for the processes and data running atop them. This in turn requires us to provide trustworthy systems. The term trustworthy is poorly defined with corresponding misunderstanding and misapplication. We present a definition of this term, as well as others, demonstrate its application against certain telecommunications use cases and address how the learnings from ontologising these structures contribute to standardisation and the necessity for FAIR ontologies across telecommunications standards and hosting organisations.