What does the term on a true mean?

The term "on a true" is not a standard English phrase. It's likely a mishearing or misspelling of a phrase with a similar sound.

Here are some possible meanings depending on the context:

* "On the true": This could be a slang expression meaning "on the right track," "accurate," or "honest."

* "On a truce": This refers to a temporary agreement to stop fighting or arguing.

* "On a true course": This could mean following a correct or planned path, especially in navigation.

To understand the intended meaning, please provide more context about where you encountered the phrase. For example, what was the conversation about? What were the surrounding words?