TBX is the LISA OSCAR standard for terminology and term exchange.
For information on more file formats, see Standards conformance.
You might also be interested in reading about TBX-Basic – a simpler, reduced version of TBX with most of the useful features included.
Additionally notes and examples about TBX are available in Terminator TBX conformance notes which might help understanding this format.
Translate Toolkit TBX format support allows:
The following are not yet supported:
<ntig>tag, read and write
Other features can be picked from the Terminator TBX conformance notes which also include examples and notes about the TBX format.