What is the meaning of ת?

Tav: the twenty-second and final letter of the Hebrew alphabet, after ש.

The numeral 400 in Hebrew numbering.

Abbreviation of תֹאַר / תואר (tó'ar, adjective): adj.

Initialism of תַּלְמוּד (Talmud), used to indicate that a term originates from the second layer of the Hebrew language: Mishnaic Hebrew

the twenty-sixth and final letter of the Yiddish alefbet

Source: wiktionary.org