In Jain usage, gatha means a verse/stanza in a scripture, stotra, or teaching text. Jain sources commonly use the word this way, such as in Bhaktamar Stotra gathas and Uvasaggaharam Stotra gathas. ( jainknowledge.com)

I could not find “Navi gatha” as a standard Jain technical term. If you mean it in ordinary language, it would most likely mean “new verse” — but that is an inference, not a fixed Jain scriptural term. ( jainknowledge.com)

If you want, I can also explain gatha in the context of a specific Jain stotra or scripture.