Suchness | Thusness
Tathata, which means "suchness" or "thusness," is a word sometimes used primarily in Mahayana Buddhism to mean "reality," or the way things really are. It's understood that the true nature of reality is ineffable, beyond description and conceptualization. "Suchness," then, is deliberately vague to keep us from conceptualizing it.
You might recognize that tathata is the root of Tathagata, which is an alternate term for "Buddha." Tathagata was the term the historical Buddha used most often to refer to himself. Tathagata can mean either "one who has thus come" or "one who has thus gone." It is sometimes translated "one who is such."
It is sometimes understood that tathata underlies reality, and the appearance of things in the phenomenal world are manifestations of tathata. The word tathata is sometimes used interchangeably with sunyata, or emptiness. While all phenomena are empty (sunyata) of self-essence, they are also full (tathata). They are "full" of reality itself, of everything.
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